• Nuclear Engineering and Technology
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• v.55 no.11
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• pp.4019-4025
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• 2023

Recently, a new monkey computational phantom, called Visible Monkey, was developed for non-ionizing radiation studies in animal research. In this study, we extended its applications to ionizing radiation studies by implementing the voxel model of the Visible Monkey into three general-purpose Monte Carlo (MC) codes: MCNP6, PHITS, and Geant4. The implementation work for MCNP and PHITS was conducted using the LATTICE, UNIVERSE, and FILL cards. The G4VNestedParameterisation class was used for Geant4. Then, organ dose coefficients (DCs) for idealized photon beams in the antero-posterior direction were calculated using the three codes and compared, showing excellent agreement (differences <3%). Additionally, organ DCs in other directions (postero-anterior, left-lateral, and right-lateral) were calculated and compared with those of the newborn and 1-year-old reference phantoms. Significant differences were observed (e.g., the stomach DC of the monkey was 5-fold greater than that of the 1-year-old phantom at 0.03 MeV) while the differences tended to decrease with increasing energy (mostly <20% at 10 MeV). The results of this study allows conducting MC simulations using the Visible Monkey to estimate organ-level doses, which should be valuable to support/improve monkey experiments involving ionizing radiation exposures.

• Journal of IKEEE
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• v.24 no.4
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• pp.1039-1049
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• 2020

Neural decoding is important to recognize the user's intention for controlling a neuro-prosthetic hand. This paper proposes a real-time decoding method for multi-channel peripheral neural activity. Peripheral nerve signals were measured from the median and radial nerves, and motion artifacts were removed based on locally fitted polynomials. Action potentials were then classified using a k-means algorithm. The firing rate of action potentials was extracted as a feature vector and its dimensionality was reduced by a self-organizing feature map. Finally, a multi-layer perceptron was used to classify hand motions. In monkey experiments, all processes were completed within a real-time constrain, and the hand motions were recognized with a high success rate.

• Journal of information and communication convergence engineering
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• v.19 no.2
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• pp.79-83
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• 2021

This paper proposes a novel image classification method based on few-shot learning, which is mainly used to solve model overfitting and non-convergence in image classification tasks of small datasets and improve the accuracy of classification. This method uses model structure optimization to extend the basic convolutional neural network (CNN) model and extracts more image features by adding convolutional layers, thereby improving the classification accuracy. We incorporated certain measures to improve the performance of the model. First, we used general methods such as setting a lower learning rate and shuffling to promote the rapid convergence of the model. Second, we used the data expansion technology to preprocess small datasets to increase the number of training data sets and suppress over-fitting. We applied the model to 10 monkey species and achieved outstanding performances. Experiments indicated that our proposed method achieved an accuracy of 87.92%, which is 26.1% higher than that of the traditional CNN method and 1.1% higher than that of the deep convolutional neural network ResNet50.

• Korean Journal of Veterinary Research
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• v.28 no.1
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• pp.115-118
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• 1988

Mating experiments were performed to, elucidate the distribution of perfect state of Microsporum gypseum complex originated from animals and soils in Korea. A total of 30 strains of M. gypseum complex, composed of 16 from animals and 14 from soils, ere mated with the tester strains of Nannizzia incurvata, N. gypsea and N. fulva. Among 30 strains of M. gypseum complex examined, 16 strains(53.3%) were N. incurvata, 13 strains(43.3%) N. gypsea and 1 strain (3.3%) N. fulva. Among 13 strains of dog isolates, 8 strains(61.5%) were N. incurvata and 5 strains(38.5%) N. gypsea. And each strain isolated from Korean native goat, monkey and albino rat was N. gypsea. Among 14 strains of soil isolates, 8 strains(57.2%) were N. incurvata, 5 strains (35.7%) N. gypsea and 1 strain(7.2%) N. fulva. And -mating type was more frequently observed than +mating type in the strains of N. incurvata and N. gypsea. By this study, N. fulva was isolated the first time in Korea.

• Proceedings of the Korean Society of Applied Pharmacology
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• 2007.04a
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• pp.25-44
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• 2007

The glucocorticoid receptor (GR) is an intracellular protein that is widely distributed throughout hippocampal and neocortical brain tissue. Mifepristone (RU486) is a potent GR antagonist that has also been shown to exhibit partial agonist-like effects. The precise location of the GR domain involved in the agonist-like activity of RU486 is unknown. Here, we examine this aspect of GR signaling by comparing human GR (hGR) construct with a Guyanese squirrel monkey GR (gsmGR) construct in which nuclear translocation and transactivation are known to be impaired. Using an objective translocation scoring method, we found that both hGR and gsmGR are translocated by RU486, and that nuclear translocation of hGR is significantly increased compared to gsmGR at 10 nM, 100 nM and 1000 nM RU486 in transiently transfected COS1 cells. While addition of RU486 to the cells transfected with hGR results in a 16-fold dose-dependent increase in transactivation compared to non-treated cells, no significant change in transactivation is observed with gsmGR at doses up to 100 nM RU486. Further experiments using six GR chimeras indicate that replacement of the hGR carboxyl-terminus of tau-1 transactivation domain (C-AF1, amino acids 132-428) with that from gsmGR diminishes hGR transactivation by RU486. These results demonstrate that RU486-induced transactivation of GR is determined in part by amino acids in the C-AF1 domain.

• Preventive Nutrition and Food Science
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• v.14 no.1
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• pp.21-28
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• 2009

In this study, we focused on natural water-soluble antioxidants from Tetraselmis suecica (T. suecica) and Chlorella ellipsoidea (C. ellipsoidea). They were prepared by enzymatic digestion using five carbohydrases (Viscozyme, Celluclast, AMG, Termamyl and Ultraflo) and five proteases (Protamex, Alcalase, Flavourzyme, Neutrase, and Kojizyme), and the potential antioxidant activity of each was assessed. Most enzymatic digests from T. suecica had a higher radical scavenging activity than those from C. ellipsoidea. Among the enzymatic digests, Kojizyme digest from T. suecica exhibited the highest effect on DPPH radical scavenging. Viscozyme (30.2%) and Neutrase (34.6%) digests from T. suecica exhibited higher hydroxyl radical scavenging activity. Kojizyme digest from T. suecica (81.5%) had strong alkyl radical scavenging activity. Neutrase (61.9%) and Kojizyme (61.5%) digest from T. suecica possessed the highest effects on hydrogen peroxide scavenging. Among the tested samples, Neutrase (TN) and Kojizyme (TK) digests from T. suecica showed the highest antioxidant activity (DPPH, alkyl radical, hydrogen peroxide). Therefore, TN and TK digests were selected for use in the further experiments. Those digests showed enhanced cell viability against $H_2O_2$-induced oxidative damage, and relatively good hydrogen peroxide scavenging activity in an African green monkey kidney (Vero) cell line. These results suggested that an enzymatic digestion will be an effective way for the production of a potential water-soluble antioxidant from a microalgae, T. suecica.

• Korean Journal of Biological Psychiatry
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• v.21 no.4
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• pp.118-127
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• 2014

Along with language, socialization is a unique feature of the human being. There is a continuous debate regarding whether the development of socialization is innate, and conducted by the environment in the growing process, or the result of the interaction of both aspects. If socialization is the result of the interaction with the environment or is an acquired developmental process, the following question rises. "Is there a 'critical period' for the development of socialization?" Although there are a huge number of studies seeking for treatment and solutions for developmental delay or deficits of socialization, it is very complicated question to answer. Historical figures such as 'Hugh Blair' of Borgue in England, and 'the wild boy of Aveyron' in France, seem to have innate socialization deficits. Nowadays patients with non-verbal learning disorder, social communication disorder, or autism spectrum disorder seem to have genetic defects. On the other hand, Harry Harlow's monkey experiments, hikikomori of Japan, Romanian orphans and patients with reactive attachment disorder seem to display social deficits due to environmental factors. However, it is not easy to clearly draw a line between innate or acquired factors. Therefore, rather than subdividing the diseases for etiological and pathophysiological approach to heterogenous groups with the common denominator of social deficit, and for the research of pathophysiology and treatment development, the authors suggest a comprehensive concept of "social dysfunction spectrum."

• Clinical and Experimental Reproductive Medicine
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• v.24 no.2
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• pp.233-239
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• 1997

Embryos of most mammalian species grown in vitro would undergo developmental arrest at the approximate time of genomic activation. Stage-specific cell block and the resulting rapid loss of embryo viability in conventional culture media have limited the duration for which embryos may be cultured prior to transfer. As a result, embryos are usually transferred to the uterus at the 4-to 8-cell stage to avoid the loss of viability associated with long-term in vitro culture. Early transfer has led to asynchrony of the endometrium-trophectoderm interaction at the time of implantation and a resultant reduction in the rate of implantation. To overcome these problems, a variety of co-culture systems has been devised in which embryos can develop for a longer period prior to embryo transfer. Vero cells, derived from African green monkey kidney, share a common embryologic origin with cells from the genital tract. In addition, they are potentially safe to use, since they are highly controlled for viruses and other contaminants. Therefore, co-culture using Vero cells has been widely utilized to enhance embryo viability and development, although not without controversies. We thus designed a series of experiments to demonstrate whether Vero cells do indeed enhance mouse embryo development as well as to compare the efficacy of co-culturing mouse 1-cell embryos on Vero cell monolayer in both Ham's F-10 and human tubal fluid (HTF) culture media. 1-cell stage ICR mouse embryos were cultured either in the presence of Vero cells (Group A) or in conventional culture medium alone (Group B). In Ham's F-10 significantly more 3-to-8cell embryos developed in group A than group B (59.8 versus 10.0%; p<0.01). In contrast, there was no significant difference in embryonic development both group A and group B in HTF. However, significant differences were noted only in later embryonic stage (13 and 0%; p<0.05 of group A and B respectively, hatching or hatched). In Ham's F-10, we also could observe the beneficial effect of Vero cell on hatching process (70.7 and 42.1%; p<0.05 of group A and group B respectively).

• Applied Microscopy
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• v.24 no.4
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• pp.61-77
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• 1994

The calcium-binding proteins (CaBP), parvalbumin (PV) and calbindin-D 28K (calbindin) are particularly abundant and specific in their distribution, and present in different subsets of neurons in many brain regions. Although their physiological roles in the neurons have not been elucidated, they are valuable markers of neuronal subpopulations for anatomical and developmental studies. This study is designed to characterize dorsal lateral geniculate nucleus (dLGN) neurons and axon terminals in terms of differential expression of immunoreactivity (IR) for two well-known CaBPs, PV and calbindin. The experiments were carried out on 6 adult monkeys. Monkeys were perfused under deep Nembutal anesthesia with 2% paraformaldehyde and 0.2% glutaraldehyde in 0.1M phosphate buffer. After removal, the brains were postfixed for 6-8 hr in 2% paraformaldehyde at $4^{\circ}C$ and infiltrated with 30% sucrose at $4^{\circ}C$. Thereafter, they were frozen in dry ice. Serial sections of the thalamus, at $20{\mu}m$, were made in the frontal plane with a sliding microtome. The sections were stained for PV and calbindin with indirect immunocytochemical methods. For electron microscopy, after infiltration with 30% sucrose the blocks of thalamus were serially sectioned at $50{\mu}m$ with a Vibratome in the coronal plane and stained immediately by indirect ABC methods without Triton X-100 in incubation medium. Stained sections were postfixed in 0.2% osmium tetroxide, dehydrated and flat-embedded in Spurr resin. The block was then trimmed to contain only a selected lamina or interlaminar space. The dLGN proper showed strong PV IR in fibers in all laminae and interlaminar zones. Particularly dense staining was noted in layers 1 and 2 that contain many stained fibers from optic tract. Neuronal cell body stained with PV was concentrated only in the laminae. In these laminae staining was moderate in cell bodies of all large and medium-sized neurons, and was strong in cell bodies of some small neurons together with their processes. Calbindin IR was marked in the neuronal cell body and neuropil in the S layers and interlaminar zones whereas moderate in the neuropil throughout the nucleus. Regional difference in distribution of PV and calbindin IR cell is distinct; the former is only in the laminae and the latter in both the S layer and interlaminar space. The CaBP-IR elements were confined to about $10{\mu}m$ in depth of Vibratome section. The IR product for CaBP was mainly associated with synaptic vesicle, pre- and post-synaptic membrane, and outer mitochondrial membrane and along microtubule. PV-IR was noted in various neuronal elements such as neuronal soma, dendrite, RLP, F, PSD and some myelinated or unmyelinated axons, and was not seen in the RSD and glial cells. Only a few neuronal components in dLGN was IR for calbindin and its reaction product was less dense than that of PV, and scattered throughout cytoplasm of soma of some relay neurons, and was also persent in some dendrite, myelinated axons and RLP. The RSD, F, PSD and glial elements were always non-IR for calbindin. Calbindin labelled RLP were presynaptic to unlabeled dendrite or dendritic spine and PSD. Calbindin-labeled dendrite of various sizes were always postsynaptic to unlabeled RSD, RLP or F. From this study it is suggested that dLGN cells of different functional systems and their differential projection to the visual cortex can be distinguished by differential expression of PV and calbindin.