• Title/Summary/Keyword: Science Laboratory Experiments

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Smoke detection in video sequences based on dynamic texture using volume local binary patterns

  • Lin, Gaohua;Zhang, Yongming;Zhang, Qixing;Jia, Yang;Xu, Gao;Wang, Jinjun
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.11 no.11
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    • pp.5522-5536
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    • 2017
  • In this paper, a video based smoke detection method using dynamic texture feature extraction with volume local binary patterns is studied. Block based method was used to distinguish smoke frames in high definition videos obtained by experiments firstly. Then we propose a method that directly extracts dynamic texture features based on irregular motion regions to reduce adverse impacts of block size and motion area ratio threshold. Several general volume local binary patterns were used to extract dynamic texture, including LBPTOP, VLBP, CLBPTOP and CVLBP, to study the effect of the number of sample points, frame interval and modes of the operator on smoke detection. Support vector machine was used as the classifier for dynamic texture features. The results show that dynamic texture is a reliable clue for video based smoke detection. It is generally conducive to reducing the false alarm rate by increasing the dimension of the feature vector. However, it does not always contribute to the improvement of the detection rate. Additionally, it is found that the feature computing time is not directly related to the vector dimension in our experiments, which is important for the realization of real-time detection.

C-Terminal Region of Ankyrin-B Interact with Z-Line Portion of Titin

  • Kim, Myong-Shin;Kim, Hyun-Suk;Park, Eun-Ran;Lee, Yeong-Mi;Lee, Min-A;Kim, Ji-Hee;Choi, Jae-Kyong;Ahn, Seung-Ju;Min, Byung-In;Shon, Myeong-Hwan;Choi, Jang-Seok;Kim, Chong-Rak
    • Biomedical Science Letters
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    • v.12 no.4
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    • pp.303-310
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    • 2006
  • Ankyrins are a ubiquitously expressed family of intracellular adaptor proteins involved in targeting diverse proteins to specialized membrane domains in both the plasma membrane and the endoplasmic reticulum. We described here that the C-terminal domain of ankyrin-B interact specifically with Z-line portion of titin in yeast two-hybrid analysis, in vitro pull-down assays and localization experiments in COS-7 cells. In this study we provide the first experimental evidence that Z-line portion of titin is necessary for the localization of ankyrin-B and ankyrin-B links between the sarcolemma and the myofibril in costameres.

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Enhanced Production of Soluble Pyrococcus furiosus α-Amylase in Bacillus subtilis through Chaperone Co-Expression, Heat Treatment and Fermentation Optimization

  • Zhang, Kang;Tan, Ruiting;Yao, Dongbang;Su, Lingqia;Xia, Yongmei;Wu, Jing
    • Journal of Microbiology and Biotechnology
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    • v.31 no.4
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    • pp.570-583
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    • 2021
  • Pyrococcus furiosus α-amylase can hydrolyze α-1,4 linkages in starch and related carbohydrates under hyperthermophilic condition (~ 100℃), showing great potential in a wide range of industrial applications, while its relatively low productivity from heterologous hosts has limited the industrial applications. Bacillus subtilis, a gram-positive bacterium, has been widely used in industrial production for its non-pathogenic and powerful secretory characteristics. This study was conducted to increase production of P. furiosus α-amylase in B. subtilis through three strategies. Initial experiments showed that co-expression of P. furiosus molecular chaperone peptidyl-prolyl cis-trans isomerase through genomic integration mode, using a CRISPR/Cas9 system, increased soluble amylase production. Therefore, considering that native P. furiosus α-amylase is produced within a hyperthermophilic environment and is highly thermostable, heat treatment of intact culture at 90℃ for 15 min was performed, thereby greatly increasing soluble amylase production. After optimization of the culture conditions (nitrogen source, carbon source, metal ion, temperature and pH), experiments in a 3-L fermenter yielded a soluble activity of 3,806.7 U/ml, which was 3.3- and 28.2-fold those of a control without heat treatment (1,155.1 U/ml) and an empty expression vector control (135.1 U/ml), respectively. This represents the highest P. furiosus α-amylase production reported to date and should promote innovation in the starch liquefaction process and related industrial productions. Meanwhile, heat treatment, which may promote folding of aggregated P. furiosus α-amylase into a soluble, active form through the transfer of kinetic energy, may be of general benefit when producing proteins from thermophilic archaea.

Assessment of the severe accident code MIDAC based on FROMA, QUENCH-06&16 experiments

  • Wu, Shihao;Zhang, Yapei;Wang, Dong;Tian, Wenxi;Qiu, Suizheng;Su, G.H.
    • Nuclear Engineering and Technology
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    • v.54 no.2
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    • pp.579-588
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    • 2022
  • In order to meet the needs of domestic reactor severe accident analysis program, a MIDAC (Module Invessel Degraded severe accident Analysis Code) is developed and maintained by Xi'an Jiaotong University. As the accuracy of the calculation results of the analysis program is of great significance for the formulation of severe accident mitigation measures, the article select three experiments to evaluate the updated severe accident models of MIDAC. Among them, QUENCH-06 is the international standard No.45, QUENCH-16 is a test for the analysis of air oxidation, and FROMA is an out-of-pile fuel rod melting experiment recently carried out by Xi'an Jiaotong University. The heating and melting model with lumped parameter method and the steam oxidation model with Cathcart-Pawel and Volchek-Zvonarev correlations combination in MIDAC could better meet the needs of severe accident analysis. Although the influence of nitrogen still need to be further improved, the air oxidation model with NUREG still has the ability to provide guiding significance for engineering practice.

Exploring Ways to Improve Integrated Science and Science Laboratory Experiments in Preparation for the 2022 Revised Curriculum (2022 개정 교육과정에 대비한 과학과 통합과학 및 과학탐구실험 교육과정 개선 방안 탐색)

  • Kwak, Youngsun;Shin, Youngjoon
    • Journal of Science Education
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    • v.45 no.2
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    • pp.143-155
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    • 2021
  • The goal of this study is to examine the Integrated Science and Science Laboratory Experiments of the 2015 revised curriculum applied since 2018, and to explore ways to improve these two subjects in preparation for the 2022 revised curriculum. A survey was conducted by randomly sampling high schools across the country, with a total of 192 science teachers participating. In addition, 12 high school science teachers were selected as focus group, and in-depth interviews were conducted to investigate ways to restructure common science courses for the next curriculum. Main research results include that most schools were operated in 6~8 units for Integrated Science, and the teachers in charge of Integrated Science per class averaged 2~3 over the three years. For Science Laboratory Experiments, it has operated for a total of two semesters, one unit per semester, and it was found that several science teachers are in charge of Science Laboratory Experiments to fill the insufficient number of hours regardless of major. In the in-depth interview, science teachers argued that Integrated Science should be reduced and restructured by strengthening key competencies in preparation for the high school credit system. Based on the research results, ways to reorganize Integrated Science focused on big ideas, ways to construct common science courses based on fundamental science concepts that can guide elective courses, the necessity of career guidance through common science courses, and the necessity of strengthening teacher professionalism for teaching interdisciplinary and multidisciplinary subjects were suggested.

Simulation study on the mechanical properties and failure characteristics of rocks with double holes and fractures

  • Pan, Haiyang;Jiang, Ning;Gao, Zhiyou;Liang, Xiao;Yin, Dawei
    • Geomechanics and Engineering
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    • v.30 no.1
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    • pp.93-105
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    • 2022
  • With the exploitation of natural resources in China, underground resource extraction and underground space development, as well as other engineering activities are increasing, resulting in the creation of many defective rocks. In this paper, uniaxial compression tests were performed on rocks with double holes and fractures at different angles using particle flow code (PFC2D) numerical simulations and laboratory experiments. The failure behavior and mechanical properties of rock samples with holes and fractures at different angles were analyzed. The failure modes of rock with defects at different angles were identified. The fracture propagation and stress evolution characteristics of rock with fractures at different angles were determined. The results reveal that compared to intact rocks, the peak stress, elastic modulus, peak strain, initiation stress, and damage stress of fractured rocks with different fracture angles around holes are lower. As the fracture angle increases, the gap in mechanical properties between the defective rock and the intact rock gradually decreased. In the force chain diagram, the compressive stress concentration range of the combined defect of cracks and holes starts to decrease, and the model is gradually destroyed as the tensile stress range gradually increases. When the peak stress is reached, the acoustic emission energy is highest and the rock undergoes brittle damage. Through a comparative study using laboratory tests, the results of laboratory real rocks and numerical simulation experiments were verified and the macroscopic failure characteristics of the real and simulated rocks were determined to be similar. This study can help us correctly understand the mechanical properties of rocks with defects and provide theoretical guidance for practical rock engineering.

Evaluating sulfoxaflor residues in pig tissues using animal modeling

  • Hyun-Woo, Cho;Kangmin, Seo;Jin Young, Jeong;Ju Lan, Chun;Ki Hyun, Kim
    • Journal of Animal Science and Technology
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    • v.64 no.5
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    • pp.911-921
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    • 2022
  • Maximum residue limits (MRL) for pesticides in feed have been set to protect public health and produce safe livestock products. In vivo experiments to establish MRL are essential, as livestock are commonly used to obtain reliable in vivo quantitative information. Here, we aimed to evaluate whether small laboratory animals can replace or reduce monogastric livestock in experiments to quantify pesticide residues in vivo after oral consumption through feed. First, 24 pigs and rats were randomly assigned to four groups and fed 0, 3, 9, or 30 mg/kg of sulfoxaflor. After four weeks, serum, muscle, fat, liver, kidney, and small intestine samples were collected, and sulfoxaflor residues were analyzed using liquid chromatography - tandem mass spectrometry. Sulfoxaflor residues in pig tissues were significantly correlated with those in rat tissues. Model equations were formulated based on the residual sulfoxaflor amount in pig and rat tissues. The calculated and measured sulfoxaflor residues in pigs and rats showed more than 90% similarity. Sulfoxaflor did not affect body weight gain, feed intake, or the feed conversion ratio. Therefore, we concluded that pesticide residue quantification in vivo to establish MRL could be performed using small laboratory animals instead of livestock animals. This would contribute to obtaining in vivo pesticide residue information and reducing large-scale livestock animal experiments.

Production of Chemistry Laboratory Class for Senior High School Freshmen

  • Yasuzawa, Mikito;Minagawa, Keiji;Kamitani, Sachiyo;Arai, Yuka;Konishi, Yuki;Nakanishi, Shinsuke;Oshima, Takuya;Yamaguchi, Junko;Ishii, Arisa
    • Journal of Engineering Education Research
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    • v.13 no.5
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    • pp.55-60
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    • 2010
  • Chemistry laboratory class was produced for senior high school freshmen with the cooperation of university staffs, high school teachers and the university students. Although the students who will take the lab class are senior high school freshmen, we decided to prepare four experiments that are simple and have highly visible reactions or transformation. That is, 1) Water purification, 2) Surface modification, 3) Briggs-Rauscher reaction, and 4) Polymer synthesis and characterization. After the safety guideline and experiment instructions by the faculty staffs, two teaching assistants (TAs) supervised each experiment. Since taking a direct part in it will provide stronger impact than only being one who is just watching the experiment, all experiments contained some process that the high school students must handle the reagents, tools or the equipment, by themselves. Although, the operation performed by the students was limited to a series of simple actions, the various unique phenomena presented by the experiments impressed the students. The lab class was fruitful not only for high school students, but also good for university students. The lab class provided good opportunity for them to improve the abilities to teach and guide someone.

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Wide-Tunable Mid Infrared Intra-cavity Optical Parametric Oscillator Based on Multi-period MgO:PPLN

  • Wang, Xiao-Chan;Wang, Yu-Heng;Zheng, Hao;Liu, Hong-Zhi;Yu, Yong-Ji;Wang, Zi-Jian
    • Current Optics and Photonics
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    • v.5 no.1
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    • pp.59-65
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    • 2021
  • This paper reports a tunable diode-pumped folded intracavity Q-switched singly resonant optical parametric oscillator based on multi-period MgO:PPLN. A wide tuning mid-infrared parametric light from 2.78 ㎛ to 4.17 ㎛ was obtained in real time by changing the poled periods and temperatures. The maximum output power of 1.89 W at 3.2 ㎛, 1.53 W at 3.5 ㎛, 0.87 W at 3.8 ㎛ and 0.486 W at 4.1 ㎛ were achieved. The highest optical-optical conversion efficiency was 7.89%. During experiments, a range tunable output of 2.78-4.17 ㎛ in the mid-infrared range was achieved.

Carbon Dioxide Adsorption Study of Biochar Produced from Shiitake Mushroom Farm by-product Waste Medium (표고버섯 농가 부산물 폐배지 기반 바이오차의 이산화탄소 흡착 연구)

  • Gyuseob Song;Jinseung Kim;Juhyoung Park;Younghoon Noh;Youngchan Choi;Youngjoo Lee;Kyubock Lee
    • New & Renewable Energy
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    • v.20 no.1
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    • pp.135-144
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    • 2024
  • The present study investigated waste medium from a domestic shiitake mushroom farm, which was pyrolyzed to produce biochar. The yield rate of the biochar was compared after exposure to various pyrolysis temperature conditions, and the characteristics of the produced biochar were analyzed. The present study focused on the carbon dioxide (CO2) adsorption capacity of the resulting biochar. The CO2 adsorption capacity exhibited a correlation with the pyrolysis temperature of the biochar, with increasing temperatures resulting in higher CO2 adsorption capacities. Brunauer-Emmett-Teller (BET) analysis showed that the CO2 adsorption capacity was related to the surface area and pore volume of the biochar. Calcium is added to the process of producing mushroom medium. Experiments were performed to investigate the CO2 adsorption capacity of the biochar from the waste medium with the addition of calcium. In addition, CO2 adsorption experiments were conducted after the pyrolysis of kenaf biochar with the addition of calcium. The results of these experiments show that calcium affected the CO2 adsorption capacity.