• Biomedical Science Letters
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• v.17 no.3
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• pp.231-238
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• 2011

During pregnancy, stress induces maternal glucocorticoid secretion, which in turn is known to affect structural malformation, retardation of growth, reduced birth weight of the fetus. As Hox genes are master transcription factors which fulfill critical roles in embryonic development, we aimed to explore the possibility that alterations of the Hox gene expression might be involved in stress-induced malformation. The pregnant mice were injected with dexamethasone at a dose of 1 mg/kg or 10 mg/kg on day 7.5, 8.5 and 9.5 p.c. (post coitum), as well as saline as control. Embryos of E11.5 and E18.5 were obtained by sacrificing pregnant animals. Weight and crown-rump length (CRL) were measured. RT-PCR was performed to examine the Hox gene expression levels. Embryos given dexamethasone at day 7.5~9.5 p.c. had small CRL and weighed less both in E11.5 and E18.5. The percentage of embryos showing abnormalities was high in groups received high dose of dexamethasone. To define the molecular basis for abnormal embryonic development, we analyzed the Hox gene expression pattern and found that many Hox genes display altered expression. Effects of prenatal dexamethasone treatment on embryonic development might be associated with the aberrant Hox gene expression.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1993.10a
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• pp.859-866
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• 1993

With the object of doing mechanical grafting of cucurbitaceous vegetables, the grafting robot was developed in 1989. This robot consists of the following components : feeding wheels, grippers, conveying wheels, cutters , fixing clipper, discharger , controller and power supply. One cycle time to produce a grafted plant is about 3 seconds, Results of some cucumber grafting tests : successful grafting rate of 98 percent and after acclimation, a successful agglutination rate of 95 percent. These techniques are now transferring to the private company. The commercial robot will come into the market in this year.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.154.1-154
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• 2001

The paper describes a new type of robot called "artificial liferobot" which is able to learn, make decisions, and behave by itself based on a brain-type computing technique called "artificial brain". The artificial liferobot has self-learning ability from the environment by the interactions between human being and it. The artificial brain makes the artificial liferobot to behave by itself with its intensions like living things as human being. We briefly introduce one attempt of our researches for developing cognitive and behavioral intelligent artificial liferobot in out laboratory. One of our purposes is the development of the artificial liferobot, which plays an Important role in taking care of elderly and infirm people in a rapidly aging society.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2018.05a
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• pp.601-603
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• 2018

Studies are under way to understand how the brain learns and how it works most effectively through the development of brain science. The purpose of this study is to apply brain - based learning principles as a way to effectively overcome the characteristics of the programming lesson and the difficulties that arise during the practice. In other words, by applying the brain-based learning principle appropriate to the characteristics of the Android programming class, the teaching and learning is designed so that the learner can effectively learn the programming.

• Transactions of the Korean Society of Automotive Engineers
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• v.4 no.4
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• pp.97-106
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• 1996

The impact response of the human brain has been determined by three-dimensional finite element modeling. The model includes a layered shell closely representing the cranial bones with the interior contents occupied by an incompressible contimuum to simulate the brain. Flax and tentorium modeled with 4 node membrane element were also incorporated. The computed pressure-time histories at 4 locations within the brain element compared quite favorably with previously published experimental data from cadaver experiments. A parametric study was subsequently conducted to identify the model response when the impact were varied.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.16 no.11
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• pp.3479-3492
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• 2022

Longitudinal quantification of brain changes due to development, aging or disease plays an important role in the filed of personalized-medicine applications. However, due to the temporal variability in shape and different imaging equipment and parameters, estimating anatomical changes in longitudinal studies is significantly challenging. In this paper, a longitudinal Magnetic Resonance(MR) brain image segmentation algorithm proposed by combining intensity information and anisotropic smoothness term which contain a spatial smoothness constraint and longitudinal consistent constraint into a variational framework. The minimization of the proposed energy functional is strictly and effectively derived from a fast optimization algorithm. A large number of experimental results show that the proposed method can guarantee segmentation accuracy and longitudinal consistency in both simulated and real longitudinal MR brain images for analysis of anatomical changes over time.

• Journal of Radiopharmaceuticals and Molecular Probes
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• v.8 no.1
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• pp.17-23
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• 2022

Boron neutron capture therapy is a precision treatment technology that selectively destroys only tumor cells by irradiating thermal neutrons after accumulating boron drugs in tumor cells. Brain tumor is difficult to diagnose and treat due to the low permeability and targeting of drugs caused by the blood-brain-barrier. Crossing the BBB is essential for drug delivery to the brain. In this study, we designed and synthesized a novel compound incorporating benzothiazole to develop a boron drug with high BBB permeability and selectivity for brain tumor cells. In addition, their potential as a BNCT drugs was evaluated.

• Molecules and Cells
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• v.27 no.5
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• pp.563-570
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• 2009

We previously isolated the OsCBT gene, which encodes a calmodulin (CaM)-binding protein, from a rice expression library constructed from fungal elicitor-treated rice suspension cells. In order to understand the function of OsCBT in rice, we isolated and characterized a T-DNA insertion mutant allele named oscbt-1. The oscbt-1 mutant exhibits reduced levels of OsCBT transcripts and no significant morphological changes compared to wild-type plant although the growth of the mutant is stunted. However, oscbt-1 mutants showed significant resistance to two major rice pathogens. The growth of the rice blast fungus Magnaporthe grisea, as well as the bacterial pathogen Xanthomonas oryzae pv. oryzae was significantly suppressed in oscbt-1 plants. Histochemical analysis indicated that the hypersensitive-response was induced in the oscbt-1 mutant in response to compatible strains of fungal pathogens. OsCBT expression was induced upon challenge with fungal elicitor. We also observed significant increase in the level of pathogenesis-related genes in the oscbt-1 mutant even under pathogen-free condition. Taken together, the results support an idea that OsCBT might act as a negative regulator on plant defense.

• Toxicological Research
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• v.23 no.3
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• pp.279-287
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• 2007

Copper (Cu) is an essential trace element indispensable for brain development and function; either excess or deficiency in Cu can cause brain malfunction. While it is known that Cu and Fe homeostasis are strictly regulated in the brain, the question as to how systemic Fe status may influence brain Cu distribution was poorly understood. This study was designed to test the hypothesis that dietary Fe condition affects Cu transport into the brain, leading to an altered brain distribution of Cu. Rats were divided into 3 groups; an Fe-deficient (Fe-D) group which received an Fe-D diet ($3{\sim}5 mg$ Fe/kg), a control group that was fed with normal diet (35mg Fe/kg), and an Fe-overload group whose diet contained an Fe-O diet (20g carbonyl Fe/kg). Following a 4-week treatment, the concentration of Cu/Fe in serum, CSF (cerebrospinal fluid) and brain were determined by AAS, and the uptake rates of Cu into choroids plexus (CP), CSF, brain capillary and parenchyma were determined by an in situ brain perfusion, followed by capillary depletion. In Fe-D and Fe-O, serum Fe level decreased by 91% (p<0.01) and increased by 131% (p<0.01), respectively, in comparison to controls. Fe concentrations in all brain regions tested (frontal cortex, striatum, hippocampus, mid brain, and cerebellum) were lower than those of controls in Fe-D rats (p<0.05), but not changed in Fe-O rats. In Fe-D animals, serum and CSF Cu were not affected, while brain Cu levels in all tested regions (frontal cortex, striatum, hippocampus, mid brain, and cerebellum) were significantly increased (p<0.05). Likewise, the unidirectional transport rate constants $(K_{in})$ of Cu in CP, CSF, brain capillary and parenchyma were significantly increased (p<0.05) in the Fe-D rats. In contrast, with Fe-O, serum, CSF and brain Cu concentrations were significantly decreased as compared to controls (p<0.05). Cu transport was no significant change of Cu transport of serum in Fe-O rats. The mRNA levels of five Cu-related transporters were not affected by Fe status except DMT1 in the CP, which was increased in Fe-D and decreased in Fe-O. Our data suggest that Cu transport into brain and ensuing brain Cu levels are regulated by systemic Fe status. Fe deficiency appears to augment Cu transport by brain barriers, leading to an accumulation of Cu in brain parenchyma.

• Animal cells and systems
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• v.1 no.3
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• pp.497-505
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• 1997

Dopamine plays diverse roles in the fetal brain development and differentiation. However, the development of the dopaminergic neurons and its receptors has not been fully understood. In our studies, in situ hybridization and immunohistochemical methods were used to investigate the ontogeny of dopaminergic neurons and its receptor subtypes during the fetal development of the rat. In situ hybridization data showed that dopamine $D_1$ and $D_2$ receptor mRNAs were expressed in the ventricular and subventricular zones of ganglionic eminence, thalamus, hypothalamus, and cortical neuroepithelium on gestational day 13. Expression of dopamine $D_1$ and $D_2$ receptors during gestational days 17 and 19 reached the same or similar level of that in the adult brain. Expression of $D_1$ receptor mRNA preceded that of $D_2$ receptor mRNA in the early developmental stage, although this pattern was reversed with the sharp increase of $D_2$ receptor mRNA soon after. $D_2$ receptor mRNA was expressed in substantia nigra of mesencephalon of the fetal rat brain. However, $D_1$ receptor mRNA was not detected in substantia nigra. Our results indicate that dopamine might function in the fetal brain during the early gestational period.