• Journal of the Korea Institute of Information and Communication Engineering
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• v.23 no.11
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• pp.1357-1363
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• 2019

In this paper, we compares the performance of the gredient descent optimizers of the Faster Region-based Convolutional Neural Network (R-CNN) model for the chromosome object detection in digital images composed of human metaphase chromosomes. In faster R-CNN, the gradient descent optimizer is used to minimize the objective function of the region proposal network (RPN) module and the classification score and bounding box regression blocks. The gradient descent optimizer. Through performance comparisons among these four gradient descent optimizers in our experiments, we found that the Adamax optimizer could achieve the mean average precision (mAP) of about 52% when considering faster R-CNN with a base network, VGG16. In case of faster R-CNN with a base network, ResNet50, the Adadelta optimizer could achieve the mAP of about 58%.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.2
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• pp.3-9
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• 1964

Root tips of wheat, soybean, cotton and barley were treated with cold temperature (12 or 24 hrs in $0^{\circ}C$ or 2$^{\circ}C$), 8-Hyd.exyquinolin (2 or 10 hrs in 0.03 or 0.1%) and colcllicine (2 or 10 hrs in 0.2 or 1, 0%), and the frequency of metaphase were observed. The results were summarized as follow; 1. Chilling the seminal roots before or after sooting from the seed significantly increased tile number of mitotic cells and the rate of metaphase cells to mitotic cells. The optimal duration of chilling seemed to be differ depending on the kinds of plant and 24 hours to be too long except wheat so far examined here. 9. 8-Hydroxyquinolin treatment, about 2 hours in 0.03%, increased the rate of metaphase cells. The higher concentration and the longer treatment of this chemical caused the lower frequency of mitotic cells generally. 3. Colchicine treatment, 2 to 10 hrs in 0.2 to 1.0%, increased the frequency of mitotic cells and the rate of metaphase cells. Colchicine treatment was same or superior than any other treatments on the increase of metaphase cells. 4. All the treatments examined here caused chromosome contraction with most serious in colchicine following by 8-Hydroxyquinolin and chilling. 5. The feasibility of general application of chilling under the check of proper temperature and proper duration depending on the kinds of crops were discussed.

• Journal of the Korean Society of Tobacco Science
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• v.18 no.1
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• pp.12-20
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• 1996

The spermatogenesis and chromosome number were investigated in the pupal testes of Helicouerpa assulta Guenee by light microscopy. During the spermatogenesis, each bundle of P8(256) sperms developed by 6 mitotic and 2 meiotic spermatogonial divisions. From the early stage of spermatogenesis, it was distinguishable between two kinds of sperm differentiation, eupyrene and apyrene spermatogenesis, which are characteristic in Lepidoptera, by the differences in nuclear shape and cell distribution in immature spermatocyst. Through the followed spermiogenesis, the spermatocysts were developed into two kinds of mature cyst, a streamline-shaped eupyrene cyst with nucleated sperms of thready head or a long spindle-shaped apyrene cyst with anucleated sperms of cylindrical head. As the results off chromosomal analysis at metaphase of the spermatogonial mitosis and spermatocytic meiosis, the chromosome number were 2n=6a/n=31, respectively, and no variation between individuals.

• The Korean Journal of Malacology
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• v.4 no.1
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• pp.42-49
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• 1988

The chromosome of Cipangopaludina chinensis malleata Chunchon area in 1988 was analysed by using aceto-orcein squash techniques of spermatogonial tissues to obtain mitotic and meiotic chromosomes. The chromosome cycle did not differ, in general, from that found in other snails, C. chinensis malleata has 18 diploid chromosomes and they were identified and classified into 2 groups. The mitotic chromosome complement of this species consists of 2 pairs of metacentric and 7 pairs of submetacentric chromosomes, Spermatogonial metaphase chromosomes range in length from 4.10 ${\mu}{\textrm}{m}$ for the largest pair to 2.20 ${\mu}{\textrm}{m}$ for the smallest pair.

• Molecules and Cells
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• v.24 no.2
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• pp.288-293
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• 2007

The conversion of mitotic chromosome into interphase chromatin consists of at least two separate processes, the decondensation of the mitotic chromosome and the formation of the higher-order structure of interphase chromatin. Previously, we showed that depletion of BAF53 led to the expansion of chromosome territories and decompaction of the chromatin, suggesting that BAF53 plays an essential role in the formation of higher-order chromatin structure. We report here that BAF53 is associated with mitotic chromosomes during mitosis. Immunostaining with two different anti-BAF53 antibodies gave strong signals around the DNA of mitotic preparations of NIH3T3 cells and mouse embryo fibroblasts (MEFs). The immunofluorescent signals were located on the surface of mitotic chromosomes prepared by metaphase spread. BAF53 was also found in the mitotic chromosome fraction of sucrose gradients. Association of BAF53 with mitotic chromosomes would allow its rapid activation on the chromatin upon exit from mitosis.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.6
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• pp.2124-2128
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• 2010

In this study, we determined effects of the mitogen-activated protein kinase (MAPK) inhibitor, U0126 on meiotic maturation, microtubule organization and actin filament assembly in the porcine oocyte. The phosphorylated MAPK was first detected at 12 h after the initiation of maturation cultures, fully activated at 24h, and remained until metaphase II. Treatment of germinal vesicle (GV) stage oocytes with $20{\mu}M$ U0126 completely blocked MAPK phosphorylation, but germinal vesicle breakdown (GVBD) was normally proceeded. However, the oocytes didn‘t progress to the metaphase I. The inhibition of MAPK resulted in abnormal spindles. In oocytes treated with U0126 after GVBD, polar body extrusion was normal, but the organization of the metaphase plate and chromosome segregation were abnormal. In conclusion, MAPK activity plays an important regulatory role in GV chromatin configuration and meiotic progress in porcine oocyte maturation.

• Journal of Plant Biology
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• v.38 no.1
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• pp.33-38
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• 1995

Hydroxyurea (HU), a DNA synthesis inhibitor, was tested as synchronizing agent in root-tip meristem of Allium wakegi. Roots were treated with 2.5mM HU for 14 h to accumulate meristem root-tip cells at the G1/S interface. After release from HU block, the cells re-entered the cell cycle with a high degree of synchrony. Synchronized mitotic frequency of A. wakegi was 22.7%, which was about 3.9 times as high as that of the control. The highest metaphase index(23.0%) was obtained when, 6 h after release from the HU block, the roots were treated with 0.05% colchicine for 2 h. Modifying various Giemsa staining protocols defined for animals and a few plant species, G-bands were visualized at prometaphase and metaphase chromosomes of A. wakegi. The higher degree of chromosome condensation, the less differential bands could be resolved. This is the first demonstration introduced partial mitotic synchronization into G-banding in plant.

• Korean Journal of Plant Taxonomy
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• v.43 no.2
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• pp.139-145
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• 2013

This study was carried out to determine the karyotype and chromosomal localizations of 45S and 5S rDNAs using FISH in Astragalus koraiensis. The somatic metaphase chromosome number of this species was 2n = 16 with basic chromosome number of x = 8. The karyotype of A. koraiensis was consisted of six pairs of median region chromosomes(chromosome 1, 3, 4, 5, 6, 8) and two pairs of submedian chromosomes(chromosome 2, 7). Based on the FISH, one pair of 45S rDNA site was detected on the centromeric region of chromosome 5. Whereas, two pair of 5S sites were detected on the short arm of chromosome 4 and centromeric region of chromosome 7, respectively. These are quite different patterns from A. membranaceus, A. membranaceus var. alpinus, and A. mongholicus. Although A. koraiensis is considered as Korean endemic species, therefore, it should be conducted out comparative FISH study with A. sikokianus and A. bhotanensis which are very similar to A. koraiensis morphologically.

• Clinical and Experimental Reproductive Medicine
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• v.24 no.3
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• pp.335-340
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• 1997

Fluorescence in situ hybridization (FISH) techniques allow the enumeration of chromosome abnormalities and from a great potential for many clinical applications. In order to produce quantitative and reproducible results, expensive tools such as a cooled CCD camera and a computer software are required. We have developed a Chromosome Image Processing System (Chips) using FISH that allows the detection and mapping of the genetic aberrations. The aim of our study, therefore, is to evaluate the capabilities of our original system using a black-and-white video camera. As a model system, three repetitive DNA probes (D18Z1, DXZ1, and DYZ3) were hybridized to variety different clinical samples such as human metaphase spreads and interphase nuclei obtained from uncultured peripheral blood lymphocytes, uncultured amniocytes, and germ cells. The visualization of the FISH signals was performed using our system for image acquisition and pseudocoloring. FISH images were obtained by combining images from each of probes and DAPI counterstain captured separately. Using our original system, the aberrations of single or multiple chromosomes in a single hybridization experiment using chromosomes and interphase nuclei from a variety of cell types, including lymphocytes, amniocytes, sperm, and biopsied blastomeres, were enabled to evaluate. There were no differences in the image quality in accordance with FISH method, fluorochrome types, or different clinical samples. Always bright signals were detected using our system. Our system also yielded constant results. Our Chips would permit a level of performance of FISH analysis on metaphase chromosomes and interphase nuclei with unparalleled capabilities. Thus, it would be useful for clinical purposes.

• Asian-Australasian Journal of Animal Sciences
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• v.2 no.1
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• pp.35-38
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• 1989

Giemsa C-banded mitotic chromosome prepatations from White Leghorn, New Hampshire and Rhode Island Red inbred lines were compared for frequency of C-band regions on individual chromosomes. Except for autosomes 3, 6, 8 and 9 and W sex chromosomes, C-banding was extremely variable in other macrochromosomes. No divergence for C-band difference between homologous chromosomes of these lines was detected. Approximately 75% of the mitotic metaphase microchromosomes have recognizable C-band regions with the current technique.