• Korean Journal of Veterinary Research
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• v.46 no.4
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• pp.305-313
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• 2006

The primary goal of the wound healing is rapid wound closure. Recent advances in cellular and molecular biology have greatly expanded our understanding of the biologic processes involved in wound repair and tissue regeneration. This study was conducted to develop a new sponge type of biomaterial to be used for either wound dressing or scaffold for tissue engineering. We designed to make a comparative study of the wound healing effect of silk fibroin/hyaluronic acid (SF/HA) blend sponge in full-thickness dermal injury model of rat. Two full-thickness excisions were made on the back of the experimental animals. The excised wound was covered with either the silk fibroin (SF), hyaluronic acid (HA) or SF/HA (7 : 3 or 5 : 5 ratio) blend sponge. On the postoperative days of 3, 7, 10 and 14, the wound area was calculated by image analysis software. Simultaneously, the tissues were stained with Hematoxylin-Eosin and Masson's trichrome methods to measure the area of regenerated epithelium and collagen deposition. In addition, we evaluated the degree of the epithelial cell proliferation using immunohistochemistry for proliferating cell nuclear antigen (PCNA). We found that the half healing time ($HT_{50}$) of SF/HA blend sponge treated groups were significantly decreased as compared with either those of SF or HA treatment group. Furthermore, SF/HA blend sponges significantly increased the size of epithelialization and collagen deposition as well as the number of PCNA positive cells on epidermal basement membrane as compared with those of control treatment. Especially, the 5 : 5 ratio group of SF/HA among all treatment groups was most effective on wound healing rate and histological studies. These results suggest that SF/HA blend sponges could accelerate the wound healing process through the increase of epithelialization, collagen deposition and basal cell proliferation in full thickness skin injury.

• Journal of Microbiology and Biotechnology
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• v.19 no.9
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• pp.858-868
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• 2009

The abundance, biomass, size distribution, and taxonomic composition of bacterial and protistan (heterotrophic and autotrophic nanoflagellates and ciliates) communities were investigated in six lakes of Masurian Lake District (north-eastern Poland) differing in trophic state. Samples were taken from the trophogenic water layer during summer stratification periods. Image analysis techniques with fluorescent in situ hybridization (FISH) as well as [$^3H$]-methyl-thymidine incorporation methods were applied to analyze differences in the composition and activity of bacterial communities. The greatest differences in trophic parameters were found between the humic lake and remaining non-humic ones. The same bacterial and heterotrophic nanoflagellate (HNF) cell size classes dominated in all the studied lakes. However, distinct increases in the contributions of large bacterial (>$1.0{\mu}m$) and HNF (>$10{\mu}m$) cells were observed in eutrophic lakes. The bacterial community was dominated by the ${\beta}$-Proteohacteria group, which accounted for 27% of total DAPI counts. Ciliate communities were largely composed of Oligotrichida. Positive correlations between bacteria and protists, as well as between nanoflagellates (both heterotrophic and autotrophic) and ciliates, suggest that concentrations of food sources may be important in determining the abundance of protists in the studied lakes.

• Journal of The Korean Society of Agricultural Engineers
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• v.58 no.2
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• pp.53-63
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• 2016

Monitoring of cyanobacteria bloom in reservoir systems is important for water managers responsible of water supply system. Cyanobacteria affect the taste and smell of water and pose considerable filtration problems at water use places. Harmful cyanobacteria bloom in reservoir have significant economic impacts. We develop a new method for estimating the cyanobacteria bloom using Landsat TM and ETM+ data. Developed model was calibrated and cross-validated with existing in situ measurements from Daecheong Reservoir's Water Quality Monitoring Program and Algae Alarm System. Measurements data of three stations taken from 2004 to 2012 were matched with radiometrically converted reflectance data from the Landsat TM and ETM+ sensor. Stepwise multiple linear regression was used to select wavelengths in the Landsat TM and ETM+ bands 1, 2 and 4 that were most significant for predicting cyanobacteria cell number and bio-volume. Based on statistical analysis, the linear models were that included visible band ratios slightly outperformed single band models. The final monitoring models captured the extents of cyanobacteria blooms throughout the 2004-2012 study period. The results serve as an added broad area monitoring tool for water resource managers and present new insight into the initiation and propagation of cyanobacteria blooms in Daecheong reservoir.

• Current Optics and Photonics
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• v.6 no.6
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• pp.598-607
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• 2022

In this paper, a simple nondestructive technology is used to investigate unstained biological blood cells in three dimensions (3D). The technology employs a reflective phase-only spatial light modulator (SLM) for displaying the phase hologram of the object being tested, and a Fourier lens for its reconstruction. The phase hologram is generated via superposing a digital random phase on the 2D image of the object. The phase hologram is then displayed by the SLM with 256 grayscale levels, and reconstructed by a Fourier lens to present the object in 3D. Since noise is the main problem in this method, the windowed Fourier filtering (WFF) method is applied to suppress the noise of the reconstructed object. The quality of the reconstructed object is refined and the noise level suppressed by approximately 40%. The technique is applied to objects: the National Institute of Standards (NIS) logo, and a film of unstained peripheral blood. Experimental results show that the proposed technique can be used for rapid investigation of unstained biological blood cells in 3D for disease diagnosis. Moreover, it can be used for viewing unstained white blood cells, which is still challenging with an optical microscope, even at large magnification.

• 한국태양에너지학회:학술대회논문집
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• 2011.04a
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• pp.25-30
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• 2011

In this paper, we analyzed the electrical characteristics with Micro-cracks in Photovoltaic module. Micro cracks are increasing the breakage risk over the whole value chine from the wafer to the finished module, because the wafer or cell is exposed to mechanical stress. And The solar cells have to with stand the stress under out door operation in the finished module. Here the mechanical stress is induced by temperature changes and mechanical loads from wind and snow. So, we experimentally analyze the direct impact of micro-cracks on the module power and the consequences after artificial aging. The first step, we made micro-cracks in PV module by mechanical load test according to IEC 61215. Next, PV modules applied the thermal cycling test, because micro-cracks accelerated aging by thermal cycling test, according to IEC61215. Before every test, we checked output and EL image of PV module. As the result of first step, we detected little power loss(0.9%). But after thermal cycling test increased power loss about 3.2%.

• The KIPS Transactions:PartB
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• v.16B no.2
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• pp.131-140
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• 2009

This paper presents a new algorithm to the segmentation of the FISH images. First, for segmentation of the cell nuclei from background, a threshold is estimated by using the gaussian mixture model and maximizing the likelihood function of gray value of cell images. After nuclei segmentation, overlapped nuclei and isolated nuclei need to be classified for exact nuclei analysis. For nuclei classification, this paper extracted the morphological features of the nuclei such as compactness, smoothness and moments from training data. Three probability density functions are generated from these features and they are applied to the proposed Bayesian networks as evidences. After nuclei classification, segmenting of overlapped nuclei into isolated nuclei is necessary. This paper first performs intensity gradient transform and watershed algorithm to segment overlapped nuclei. Then proposed stepwise merging strategy is applied to merge several fragments in major nucleus. The experimental results using FISH images show that our system can indeed improve segmentation performance compared to previous researches, since we performed nuclei classification before separating overlapped nuclei.

• Journal of the Korean Institute of Telematics and Electronics T
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• v.35T no.3
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• pp.103-112
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• 1998

This paper proposes a propagation prediction model which can calculate a propagation path loss easily at option point in case of the propagation processing by repeat reflection when we analysis a propagation route, it makes the calculation speed which is the defect of a geometrical of image method and a ray-launching method improve and we develop and apply the algorithms which can do an angle of incidence, an angle of reflection with a propagation direct path, a reflection path and a maximum reflection number arithmetic process synchronously. Finally we choose as a sample which is the real road condition where is around SK telecoms chunnam branch office in wolgok-dong, kwangsan-ku, kwangju and simulate proposition model then we demonstrate the relative superiority with comparing the results.

• Proceedings of the KSAR Conference
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• 2001.03a
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• pp.37-37
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• 2001

포유동물의 정자형성과정 (spermatogenesis) 은 유사분열과 감수분열이 동시에 일어나는 매우 복잡하지만, 효율적으로 생식세포를 증식, 분화시키는 시스템이다 정상적인 spermatogenesis가 일어나는 testis에서는 haploid (IN), diploid (2N), 그리고 tetraploid(4N)과 같은 핵형을 갖는 세포들이 일정한 비율로 존재한다. DNA flow cytometry(DNA FCM) 는 세포의 핵형(ploidy)을 신속·정확하게 측정하여, 1N, 2N 그리고 4N에 대한 비율을 예측할 수 있어서, 생식세포를 포함한 다양한 유형의 세포주기를 분석하는데 적용되어져 왔다. 세포주기 분석법 중 이와 같은 FCM이외에, flow cytometer와 static image cytometer를 결합시켜 새롭게 고안된 laser scanning cytometer (LSC)가 있다. 그리고, 이제까지 LSC를 사용한 spermatogenesis에 관한 연구에 대해서는 보고된 바가 없다. 본 실험은 설치류에 있어 각기 다른 발달단계에 있는 정상적인 정소세포를 분리하여 PI (propidium iodide) 로 DNA를 염색한 후, DNA함량을 LSC로 분석하였다. 이것을 FCM에 의한 정소세포의 DNA분석과 비교·검토하였으며, 이 방법을 정상적인 spermatogenesis 가 일어나지 않는 동물시스템에 적용시켰다. 생식세포를 소멸시키기 위해 항암제인 busulfan과 비타민 A를 결핍시켜 이것이 세포주기의 어떤 시점에서 어떻게 작용하여, 생식세포를 소멸시키는지 알아보았다. 위의 실험·분석결과로부터 LSC를 사용한 DNA함량과 핵형의 결정은 FCM과 동일한 수준의 정확성을 제시하였다. busulfan 또는 비타민 A의 결손은 살아있는 세포의 80% 이상이 2N의 핵형에 해당하는 G0/G1 기에 있는 것으로 나타났다. 그리고 1N:2N 및 4N:2N의 핵형비율의 변화를 가져왔다. 이러한 자극은 생식세포주기제어에 관여하며, 생식세포가 증폭하고 분화로 들어가는 단계를 차단, G0/G1 기에서 정체(arrest)되는 것으로 시사된다.

• Clinical and Experimental Pediatrics
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• v.49 no.4
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• pp.439-445
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• 2006

Purpose : ${\alpha}$-Galactosylceramide (${\alpha}$-GalCer)-stimulated human $V{\alpha}24$ natural killer T (NKT) cells exert antitumor activity against some leukemia in a CD1d dependent and TCR-mediated manner, but could not kill CD1d - negative neuroblastoma (NB) cells. There are few reports about the direct antitumor effect of highly secreted cytokines by these cells on activation. In this study, using a cell-free supernatant (SPN) collected from plate bound hCD1d/${\alpha}$ GalCer tetramers-stimulated NKT cells, we examined whether they could be helpful in the immunotherapeutic treatment of NB. Methods : Cells were cultured in IMDM. The cytokines produced by NKT cells were measured with Cytometric Bead Array (CBA) analysis. Cell viability was evaluated by calcein-AM fluorescence with digital image microscopy scanning (DIMSCAN). The percentage of specific apoptosis was calculated by flow cytometric detection of apoptosis using annexin V and 7-AAD. Results : The activated NKT cells secreted high levels of IL-2, INF-${\gamma}$, TNF-${\alpha}$. The SPN was significantly cytotoxic against four out of eight tested NB cell lines, through mainly apoptosis as evidenced by annexin-V staining and inhibition with the pretreatment of pancaspase blocker. This apoptosis was significantly inhibited when anti-TNF-${\alpha}$ and anti-IFN-${\gamma}$ neutralizing mAbs were used separately and it was completely abolished when the two mAbs were combined. Conclusion : IFN-${\gamma}$ and TNF-${\alpha}$ produced by NKT cells could exert synergistically direct antitumor activity through apoptosis on some NB cell lines.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.18
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• pp.8293-8298
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• 2016

Background: Urinary stones are known predisposing factors for upper urinary tract carcinoma (UUTC) which are commonly detected at advanced stage with poor outcome because of rarity and lack of specific criteria for early detection. Aims and objectives: The main aim was to evaluate the impact of age, gender andstone characteristics on risk of developing UUTC in patients with chronic nephrolithiasis. We also discuss the role of aberrant angiogenesis (AA) and immunohistochemical expression of p53, p16INK4a, CK20 and Ki-67 in diagnosis of pelvicalyceal neoplastic (NL) and pre-neoplastic lesions (PNL) in these patients. Materials and Methods: Retrospective analysis of pelvicalyceal urothelial lesions from 88 nephrectomy specimens were carried out in a tertiary care centre from June 2012 to December 2014. Immunohistochemistry (IHC) was performed on 37 selected cases. Computed image analysis was performed to analyse aberrant angiogenesis. Results: All UUTC (5.7%) and metaplastic lesions were found to be associated with stones. Some 60% were pure squamous cell carcinoma and 40% were transitional cell carcinoma. Odd ratios for developing NL and PNL lesions in presence of renal stone, impacted stones, multiple and large stag horn stones were 9.39 (95% CI 1.15-76.39, p value 0.05), 6.28 (95% CI 1.59-24.85, p value 0.000) and 7.4 (95% CI, 2.29-23.94, p value 0.001) respectively. When patient age was ${\geq}55$, the odds ratio for developing NL was 3.43 (95% CI 1.19-9.88, p value 0.019). IHC analysis showed that mean Ki-67 indices were $3.15{\pm}3.63%$ for non-neoplastic lesions, $10.0{\pm}9.45%$ for PNL and $28.0{\pm}18.4%$ for NL. Sensitivity and specificity of CK20, p53, p16INK4a, AA were 76% and 95.9%; 100% and 27.5%; 100% and 26.5%; 92.3 % and 78.8% respectively. Conclusions: Age ${\geq}55years$, large stag horn stones, multiple stones and impacted stones are found to be associated with increased risk of NL and PNL in UUT. For flat lesions, a panel of markers, Ki 67 index >10 and presence of aberrant angiogenesis were more useful than individual markers.