• Asian Journal of Innovation and Policy
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• 제11권1호
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• pp.30-49
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• 2022

As industrialized countries transition into knowledge economies, there is a rising demand for talent and innovation. Support for start-ups through incubation, acceleration, and venture capital has turned into a key area of investment, with public and private actors searching for the next unicorn. This article examines start-up visas as an emerging policy tool in the global competition for highly innovative entrepreneurs. The study builds on a sample of eight national start-up immigration programs and applies human-capital citizenship (Ellermann, 2020) as a guiding framework. The article first proposes a conceptualization of start-up visas, suggesting that innovation and entrepreneurship also be considered in the theorization of skills. Second, the study examines the implications of start-up visas for international mobility. By focusing on the logic of entry requirements and subsequent benefits accrued through the status as a start-up founder, the findings of this study highlight the role of start-up visas in expanding privileged pathways to cross-border mobility. The article concludes with a discussion of implications for policy and research concerned with the international mobility of start-ups

• Journal of Plant Biotechnology
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• 제45권4호
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• pp.322-327
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• 2018

Post-translational modification of proteins regulates signaling cascades in eukaryotic system, including plants. Among these modifications, phosphorylation plays an important role in modulating the functional properties of proteins. Plants perceive environmental cues that directly affect the phosphorylation status of many target proteins. To determine the effect of environmentally induced phosphorylation in plants, in vivo methods must be developed. Various in vitro methods are available but, unlike in animals, there is no optimized methodology for detecting protein phosphorylation in planta. Therefore, in this study, a robust, and easy to handle Phos-Tag Mobility Shift Assay (PTMSA) is developed for the in vivo detection of protein phosphorylation in plants by empirical optimization of methods previously developed for animals. Initially, the detection of the phosphorylation status of target proteins using protocols directly adapted from animals failed. Therefore, we optimized the steps in the protocol, from protein migration to the transfer of proteins to PVDF membrane. Supplementing the electrophoresis running buffer with 5mM $NaHSO_3$ solved most of the problems in protein migration and transfer. The optimization of a fast and robust protocol that efficiently detects the phosphorylation status of plant proteins was successful. This protocol will be a valuable tool for plant scientists interested in the study of protein phosphorylation.

• Current Photovoltaic Research
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• 제10권1호
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• pp.16-22
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• 2022

The long-term stability of PSCs against visual and UV light, moisture, electrical bias and high temperature is an important issue for commercialization. In particular, since the operation temperature of solar cell can rise above 85℃, a study on thermal stability is required. In this study, the cause of thermal-induced degradation of PSCs was investigated using the SCAPS-1D simulation tool. First, PSCs of TiO₂/CH₃NH₃PbI₃/Spiro-OMeTAD/Au structure were exposed to a constant temperature of 85℃ to observe changes in conversion efficiency and quantum efficiency. Because the EQE reduction above 500 nm was remarkable, we simulated PSCs performance as a function of lifetime, doping density of perovskite and spiro-OMeTAD. Consequently, the main cause of thermal-induced degradation is considered to be the change in the perovskite doping concentration and lifetime due to ion migration of perovskite.

• International Journal of Stem Cells
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• 제15권4호
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• pp.359-371
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• 2022

Background and Objectives: The goal of this study was to investigate the mechanism of mesenchymal stem cell (MSC)-derived microRNA (miR)-150-5p-expressing exosomes in promoting skin wound healing through activating PI3K/AKT pathway by PTEN. Methods and Results: Human umbilical cord (HUC)-MSCs were infected with miR-150-5p overexpression and its control lentivirus, and HUC-MSCs-derived exosomes (MSCs-Exos) with stable expression of miR-150-5p were obtained. HaCaT cells were induced by H₂O₂ to establish a cellular model of skin injury, in which the expression of miR-150-5p and PTEN and the phosphorylation of PI3K and AKT were evaluated. HaCaT cells were transfected with pcDNA3.1-PTEN or pcDNA3.1 and then cultured with normal exosomes or exosomes stably expressing miR-150-5p. Cell proliferation was inspected by CCK-8. Cell migration was detected by scratch test and cell apoptosis by flow cytometry. The starBase tool was used to predict the binding site of miR-150-5p to PTEN. Dual-luciferase reporter assay and RIP assay were applied to assess the interaction between miR-150-5p and PTEN. In H₂O₂-induced HaCaT cells, the miR-150-5p expression decreased, and PTEN expression increased in a concentration-dependent manner. MSCs-Exos promoted the growth and migration of H₂O₂-induced HaCaT cells and inhibited their apoptosis. In addition, overexpression of exosomal miR-150-5p enhanced the protective effect of MSCs-Exos on H₂O₂-induced HaCaT cells; PTEN overexpression in HaCaT cells partially restrained miR-150-5p-mediated inhibition on H₂O₂-induced injury in HaCaT cells. PTEN was a target gene of miR-150-5p. MiR-150-5p regulated PI3K/AKT pathway through PTEN. Conclusions: MSCs-derived miR-150-5p-expressing exosomes promote skin wound healing by activating PI3K/AKT pathway through PTEN.

• 한국발생생물학회:학술대회논문집
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• 한국발생생물학회 2001년도 발생공학 국제심포지움 및 학술대회 발표자료집
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• pp.14-17
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• 2001

Positional clonging (map-based cloning) of mutations or genetic variations has been served as an invaluable tool to understand in-vivo functions of genes and to identify molecular components underlying phenotypes of interest. Mice homozygous for the cerebellar deficient folia (cdf) mutation are ataxic, with cerebellar hypoplasia and abnormal lobulation of the cerebellum. In the cdf mutant cerebellum approximately 40% of Purkinje cells are ectopically located within the white matter and the inner granule cell layer (IGL). To identify the cdf gene, a high-resolution genetic map for the cdf-gene-encompassing region was constructed using 1997 F2 mice generated from C3H/HeSnJ-cdf/cdf and CAST/Ei intercross. The cdf gene showed complete linkage disequilibrium with three tightly linked markers D6Mit208, D6Mit359, and D6Mit225. A contig using YAC, BAC, and P1 clones was constructed for the cdf critical region to identify the gene. A deletion in the cdf critical region on chromosome 6 that removes approximately 150 kb of DNA selection. cdf mutant mice with the transgenic copy of the identified gene restored the brain abnormalities of the mutant mice. The positional cloning of cdf gene provides a good example showing the identification of a gene could lead to finding a new component of important molecular pathways.

• Biomolecules & Therapeutics
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• 제26권4호
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• pp.380-388
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• 2018

Neural stem cells (NSCs) have the ability to self-renew and differentiate into multiple nervous system cell types. During embryonic development, the concentrations of soluble biological molecules have a critical role in controlling cell proliferation, migration, differentiation and apoptosis. In an effort to find optimal culture conditions for the generation of desired cell types in vitro, we used a microfluidic chip-generated growth factor gradient system. In the current study, NSCs in the microfluidic device remained healthy during the entire period of cell culture, and proliferated and differentiated in response to the concentration gradient of growth factors (epithermal growth factor and basic fibroblast growth factor). We also showed that overexpression of ASCL1 in NSCs increased neuronal differentiation depending on the concentration gradient of growth factors generated in the microfluidic gradient chip. The microfluidic system allowed us to study concentration-dependent effects of growth factors within a single device, while a traditional system requires multiple independent cultures using fixed growth factor concentrations. Our study suggests that the microfluidic gradient-generating chip is a powerful tool for determining the optimal culture conditions.

• 기술혁신연구
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• 제13권2호
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• pp.179-205
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• 2005

This study reveals that the user industry has a limited role in being a source of technological capability in the case of the machine tool industry in Korea where the user industry is relatively more advanced than other capital goods industries. This study examines the sources of technological capability in terms of migration of workforces and flow of product development knowledge. Although the capital goods sector is generally regarded as being the sector where user-producer interaction is important, the user industry is not the seed-bed of technological capability for machine development. Users and producers interact in terms of expressing 'needs', mainly in the form of specifications. As a result of receiving unique specifications from users, the producer learns to react by making specific customised special purpose machines. The user's specification could include information o the imported machine originally used. When confronted with technical problems in developing a new machine, the producer accesses foreign sources of knowledge. This study's finding reveals that users of special purpose machines have a significantly clearer role in providing specifications than do users of general purpose machine tools. Most intensive interactive learning between users and producers in the production process is found in special purpose machine tools. From the empirical findings, policy implications are discussed.

• 대한지리학회지
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• 제32권2호
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• pp.229-244
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• 1997

개혁 이전에 정책적으로 강력히 억제된 중국의 도시화는 개혁 이후 상품 경제의 발달로 변화되었다. 그 과정에서 농촌 중심지인 소성진이, 급격한 도시화를 막고 농업부문의 잉여노동력을 흡수할 수 있는 역할이 부각되어 양적ㆍ질적인 성장을 하였다. 소성진은 농업부문의 구조조정, 농촌 공업화의 규모화, 잉여 노동력의 해소의 역할을 하면서 한편으로는 왜곡된 중국 취락 체계의 회복과 상품경제로 성장한 농촌주민들의 도시 진입 욕구를 해결하는 도구로서 작용하였다. 소성진화 과정은 비록 과도적 단계이지만 공간 정책을 통해 전반적인 사회의 혼란을 최소화하는 긍정적인 역할을 수행하고 있다.

• 대한치과의사협회지
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• 제48권10호
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• pp.738-753
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• 2010

Objectives: To deter job migration and to facilitate a more efficient personnel management system, a personality type analysis tool, such as MBTI and Enneagram, may be considered. These tools can facilitate better recognition of talent among prospective employees, as well as more efficient allocation of tasks for greater job satisfaction. Methods: This study conducted direct interviews with dental hygienists currently employed at two major dental organizations, which operate the largest networks of clinics across the greater metropolitan area. Results : First, in terms of number of turnover experiences, the Head Type showed lower task satisfaction, whereas the Body Type exhibited greater task satisfaction. Second, the Head Type showed greater job satisfaction compared to the other types. Third, the SJ Type, often considered the traditionalist in terms of long-term employments, exhibited greater tendencies toward long-term commitment with one employer. Fourth, dental hygienists, in terms of long-term employment, are negatively affected by task satisfaction, and positively affected by job satisfaction. Conclusions: It is thought to be considerable to use personality type analysis tools in clinical human resource management.

• 생약학회지
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• 제45권2호
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• pp.127-134
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• 2014

A great interest is emerging about green tea as a tool against human cancer proliferation or inflammation, as pointed out by recent reports describing the inhibitory action of epigallocatechin gallate (EGCG) on angiogenesis, urokinase, metalloproteinases, and induction of inducible nitric oxide synthase. We proposed that EGCG may regulate a multi target signaling having wider spectra of action than those actions of single enzymes. CSK (c-terminal Src kinase) protein is a non-receptor tyrosine kinase involved in the cross-talk and mediation of many signaling pathways that promote cell proliferation, adhesion, invasion, migration, and tumorigenesis. Based on the knowledge that CSK activation is important for cancer proliferation we hypothesized that CSK could be a target of EGCG. Here we showed that EGCG effectively suppressed the growth of CSK MEF cell when compare with CSK knockout MEF cell growth. These results indicate that EGCG could be used as a chemoprevention to modulate CSK signal pathway in inflammatory processes and tumor formation.