• Journal of Ocean Engineering and Technology
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• v.23 no.6
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• pp.39-43
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• 2009

A flow and low temperature of deep seawater the biofouling properties in a seawater environment of different materials, such as a steel pipe, polyethylene pipe, and nylon net, used for ocean industries. Experiments in a real sea environment were performed to grasp the quantitative and qualitative biofouling from diatoms attached to materials by measuring the Chlorophyll-a density. Experimental samples were placed under five types of ocean environmental conditions and analyzed every month for five months. It is shown that the biofouling by diatoms was strongly affected by the seawater temperature for all of the experimental samples. It was found that diatoms mainly adhered to the nylon net, while crustaceans prefer polyethylene, under a high temperature condition. It is believed that the biofouling properties are strongly related to the surface roughness of a material. The biofouling under the low temperature condition of deep seawater was rare and stable for the experimental periods. The inside of a pipe conveying deep seawater can be presumed to remain clear without biofouling on the condition of a flow and low temperature of deep seawater.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.15
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• pp.6257-6261
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• 2014

Background: HPV related cervical cancer as one of the most common women cancers in developing countries. Regarding accessibility of commercial vaccines, any long or short term modality for integrating preventive immunization against HPV in a national program needs comprehensive information about HPV prevalence and its genotypes. The important role of selecting most accurate diagnostic technologies for obtaining relevant data is underlined by different assays proposed in the literature. The main objective of the present study was to introduce an in-house HPV typing assay using multiplex real time PCR with reliable results and affordable cost for molecular epidemiology surveys and diagnosis. MATERIALS AND METHODS: 112 samples of formalin fixed paraffin embedded tissues and liquid based cytology specimens from patients with known different grades of cervical dysplasia and invasive cancer, were examined by this method and the result were verified by WHO HPV LabNet proficiency program in 2013. RESULTS: HPV was detected in 105 (93.7%) out of 112 samples. The dominant types were HPV 18 (61.6%) and HPV 16 (42.9%). Among the mixed genotypes, HPV 16 and 18 in combination were seen in 12.4% of specimens. CONCLUSIONS: According to acceptable performance, easy access to primers, probes and other consumables, affordable cost per test, this method can be used as a diagnostic assay in molecular laboratories and for further planning of cervical carcinoma prevention programs.

• ALGAE
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• v.31 no.2
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• pp.167-174
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• 2016

Biological response of cells to variable conditions should affect the expression level of certain genes. Quantification of these changes in target genes needs stable internal controls. Real-time quantitative polymerase chain reaction (PCR) has traditionally used reference or ‘housekeeping’ genes, that are considered to maintain equal expression in different conditions, to evaluate changes in target genes between samples and experimental conditions. Recent studies showed that some housekeeping genes may vary considerably in certain biological samples. This has not been evaluated in red algae. In order to identify the optimal internal controls for real-time PCR, we studied the expression of eleven commonly used housekeeping genes; elongation factor 1-alpha, glyceraldehyde-3-phosphate dehydrogenase, β-actin, polyubiquitin, 30S ribosomal gene, 60S ribosomal gene, beta-tubulin, alpha-tubulin, translation initiation factor, ubiquitin-conjugating enzyme, and isocitrate dehydrogenase in different life-history stages of Bostrychia moritziana. Our results suggest that glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and 30S ribosomal gene, have the most stable gene expression levels between the different life history stages (male, female, carposporophyte, and tetrasporophyte), while the other genes are not satisfactory as internal controls. These results suggest that the combinations of GAPDH and 30S would be useful as internal controls to assess expression level changes in genes that may control different physiological processes in this organism or that may change in different life history stages. These results may also be useful in other red algal systems.

• The Mathematical Education
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• v.55 no.3
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• pp.317-334
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• 2016

Knowledge and data interpretation on statistical estimation was important to have statistical literacy that current curriculum was said not to satisfy. The author investigated mathematics teachers' MKT on statistical estimation concerning interpretation of confidence interval by using questionnaire and interview. SMK of teachers' confidence was limited to the area of textbooks to be difficult to interpret data of real life context. Most of teachers wrongly understood SMK of interpretation of confidence interval to have influence upon PCK making correction of students' wrong concept. SMK of samples and sampling distribution that were basic concept of reliability and confidence interval cognized representation of samples rather exactly not to understand importance and value of not only variability but also size of the sample exactly, and not to cognize appropriateness and needs of each stage from sampling to confidence interval estimation to have great difficulty at proper teaching of statistical estimation. PCK that had teaching method had problem of a lot of misconception. MKT of sample and sampling distribution that interpreted confidence interval had almost no relation with teachers' experience to require opportunity for development of teacher professionalism. Therefore, teachers were asked to estimate statistic and to get confidence interval and to understand concept of the sample and think much of not only relationship of each concept but also validity of estimated values, and to have knowledge enough to interpret data of real life contexts, and to think and discuss students' concepts. So, textbooks should introduce actual concepts at real life context to make use of exact orthography and to let teachers be reeducated for development of professionalism.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.4
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• pp.662-666
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• 2011

In this study, distribution characteristics of dioxins in soils in Busan, Korea were investigated regarding different land use types. Soil sampling sites that distributed through the Busan city showed dioxin concentration ranging from 0.489 to $322.736pg-TEQ\;g^{-1}$ dry weight with a mean value of $26.257pg-TEQ\;g^{-1}$ dry weight. The mean dioxin concentrations of investigated soils ranged from 1.554 to $50.357pg-TEQ\;g^{-1}$ dry weight in consideration of each land use type. That in metal refinery sites with $50.357pg-TEQ\;g^{-1}$ dry weight was higher than any other sites, followed by waste incinerator sites with $44.285pg-TEQ\;g^{-1}$ dry weight. The majority of soil samples had the same dioxin congener profiling despite the different range of dioxin concentration. Octa-CDD was the major contributor among seventeen dioxin congeners with the range from 29.5 to 70.1% in real values. In contrast to real values, dioxin congener profiles in TEQ values were dominated by 2,3,4,7,8-PeCDF which contributed about 35.3~43.8% to the total dioxin concentrations. It was judged by these results that penta-CDF was the major contributor of soil samples in Busan city. The mean ratio of PCDFs/PCDDs in real values was about 0.71, but that in TEQ values was, in contrast to it, approximately 3.03.

• Korean Journal of Veterinary Service
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• v.46 no.2
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• pp.123-135
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• 2023

Feline calicivirus (FCV) is considered the main viral pathogen of feline upper respiratory tract disease (URTD). The frequent mutations of field FCV strains result in the poor diagnostic sensitivity of previously developed molecular diagnostic assays. In this study, a more sensitive real-time reverse transcription-polymerase chain reaction (qRT-PCR) assay was developed for broad detection of currently circulating FCVs and comparatively evaluated the diagnostic performance with previously developed qRT-PCR assay using clinical samples collected from Korean cat populations. The developed qRT-PCR assay specifically amplified the FCV p30 gene with a detection limit of below 10 copies/reaction. The assay showed high repeatability and reproducibility, with coefficients of intra-assay and inter-assay variation of less than 2%. Based on the clinical evaluation using 94 clinical samples obtained from URTD-suspected cats, the detection rate of FCV by the developed qRT-PCR assay was 47.9%, which was higher than that of the previous qRT-PCR assay (43.6%). The prevalence of FCV determined by the new qRT-PCR assay in this study was much higher than those of previous Korean studies determined by conventional RT-PCR assays. Due to the high sensitivity, specificity, and accuracy, the new qRT-PCR assay developed in this study will serve as a promising tool for etiological and epidemiological studies of FCV circulating in Korea. Furthermore, the prevalence data obtained in this study will contribute to expanding knowledge about the epidemiology of FCV in Korea.

• International Journal of Computer Science & Network Security
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• v.23 no.7
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• pp.186-192
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• 2023

Malwares are becoming a major problem nowadays all around the world in android operating systems. The malware is a piece of software developed for harming or exploiting certain other hardware as well as software. The term Malware is also known as malicious software which is utilized to define Trojans, viruses, as well as other kinds of spyware. There have been developed many kinds of techniques for protecting the android operating systems from malware during the last decade. However, the existing techniques have numerous drawbacks such as accuracy to detect the type of malware in real-time in a quick manner for protecting the android operating systems. In this article, the authors developed a hybrid model for android malware detection using a decision tree and KNN (k-nearest neighbours) technique. First, Dalvik opcode, as well as real opcode, was pulled out by using the reverse procedure of the android software. Secondly, eigenvectors of sampling were produced by utilizing the n-gram model. Our suggested hybrid model efficiently combines KNN along with the decision tree for effective detection of the android malware in real-time. The outcome of the proposed scheme illustrates that the proposed hybrid model is better in terms of the accurate detection of any kind of malware from the Android operating system in a fast and accurate manner. In this experiment, 815 sample size was selected for the normal samples and the 3268-sample size was selected for the malicious samples. Our proposed hybrid model provides pragmatic values of the parameters namely precision, ACC along with the Recall, and F1 such as 0.93, 0.98, 0.96, and 0.99 along with 0.94, 0.99, 0.93, and 0.99 respectively. In the future, there are vital possibilities to carry out more research in this field to develop new methods for Android malware detection.

• Journal of Microbiology and Biotechnology
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• v.33 no.8
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• pp.1091-1100
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• 2023

Human papillomavirus (HPV) types 16 and 18 are the major causes of cervical lesions and are associated with 71% of cervical cancer cases globally. However, public health infrastructures to support cervical cancer screening may be unavailable to women in low-resource areas. Therefore, sensitive, convenient, and cost-efficient diagnostic methods are required for the detection of HPV16/18. Here, we designed two novel methods, real-time ERA and ERA-LFD, based on enzymatic recombinase amplification (ERA) for quick point-of-care identification of the HPV E6/E7 genes. The entire detection process could be completed within 25 min at a constant low temperature (35-43℃), and the results of the combined methods could be present as the amplification curves or the bands presented on dipsticks and directly interpreted with the naked eye. The ERA assays evaluated using standard plasmids carrying the E6/E7 genes and clinical samples exhibited excellent specificity, as no cross-reaction with other common HPV types was observed. The detection limits of our ERA assays were 10⁰ and 10¹ copies/µl for HPV16 and 18 respectively, which were comparable to those of the real-time PCR assay. Assessment of the clinical performance of the ERA assays using 114 cervical tissue samples demonstrated that they are highly consistent with real-time PCR, the gold standard for HPV detection. This study demonstrated that ERA-based assays possess excellent sensitivity, specificity, and repeatability for HPV16 and HPV18 detection with great potential to become robust diagnostic tools in local hospitals and field studies.

• Korean Journal of Veterinary Service
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• v.35 no.3
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• pp.215-222
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• 2012

Species-specific $TaqMan^{(R)}$ probe-based real-time PCR assays were developed for detection of beef, pork, chicken, duck, goose and turkey. The primer and probe sets used in this study were designed to be complementary to fibroblast growth factor (FGF) for cattle and pig, mitochondrial NADH dehydrogenase (ND) subunit 3 and ND2 for chicken and duck, 12S rRNA for goose and turkey, respectively. As internal positive control we used conserved region in the ribosomal 18S RNA gene to ensure the accuracy of the detection of target DNA by real-time PCR. We confirmed that real-time PCR assays with the primer and probe sets were positive for cattle, pig and chicken intended target animal species with no cross-reactivity with other non-target animal species. Only >50 ng DNA of beef show cross-reactivity in the determination of duck. Using species-specific primer and probe sets, it was possible to detect amounts of 0.1 ng DNA of cattle and pig, 1.0 pg DNA of chicken, duck and turkey, and 0.1 pg DNA of goose for raw samples, respectively. The detection limits were 0.1 ng DNA of cattle, 1.0 ng DNA of pig and 1.0 pg DNA of chicken for DNA mixtures (beef, pork and chicken) extracted from heat-treated ($121^{\circ}C$/5 min) meat samples. In conclusion, it can be suggested that the $TaqMan^{(R)}$ probe-based assay developed in this study might be a rapid and specific method for the identification of meat species in raw or cooked meat products.

• Journal of Microbiology and Biotechnology
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• v.16 no.11
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• pp.1778-1783
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• 2006

Event-specific PCR detection methods are the primary trend in genetically modified (GM) plant detection owing to their high specificity based on the flanking sequence of the exogenous integrant. Therefore, this study describes a real-time PCR system for event-specific GM canola GT73, consisting of a set of primers, TaqMan probe, and single target standard plasmid. For the specific detection of GT73 canola, the 3'-integration junction sequence between the host plant DNA and the integrated specific border was targeted. To validate the proposed method, test samples of 0, 1, 3, 5, and 10% GT73 canola were quantified. The method was also assayed with 15 different plants, and no amplification signal was observed in a real-time PCR assay with any of the species tested, other than GT73 canola.