나트륨 아지드와 금속산화물과의 혼합물에 대한 열분해 특성

설수덕,최재욱,이내우,박광수,왕석주 한국산업안전학회 1997 한국안전학회지 Vol.12 No.3

The thermal characteristics of two binary mixtures by sodium azide/manganese dioxide and ferric oxide, two ternary mixtures by sodium azide/silicon dioxide/manganese dioxide and ferric oxide were studied to obtain the basic data of gas-generating agents for air bags. The thermal reaction for all mixtures started at about 420℃, but the temperature at which the reaction rate reached a maximum was different with the states of samples. According to reaction results, nitrogen, nitrogen oxide and nitrogen dioxide were detected by GC-MS and so many kinds of new chemicals from sodium azide and metal oxide mixtures by XRD. NMS is considered as most stable and reasonable mixture for this types of gas-generating agents.

탄수화물의 종류가 IN VITRO 반추위박테리아에 의한 OLEIC ACID 의 HYDROGENATION 및 INCORPORATION 에 미치는 효과

송만강,왕제휘,최향순 한국영양사료학회 1999 韓國營養飼料學會誌 Vol.23 No.6

본 시험은 첨가하는 탄수화물의 종류가 반추위 박테리아에 의한 발효특성, 박테리아 성장 및 oleic acid(C_(18:1))의 hydrogenation과 박테리아 lipid로의 incorporation을 조사하고자 in vitro 방법으로 실시 되었다. 200㎖ non-selective basal broth medium에 dextrose, starch 또는 cellulose powder를 0.20%로(w/v) 첨가하였으며, 탄수화물이 첨가되지 않은 control을 포함한 4처리 각각을 위해 nylon 천(2×3㎝)을 이용하여 평균 87.4㎎의 C_(18:1) 과 I^-(14)C_(18:1) 2.09uCi를 흡착시켰다. Oleic acid와 각각의 탄수화물이 첨가된 broth medium에 8겹의 cheese cloth로 여과시킨 반추위액 3㎖를 첨가하여 혐기적인 방법으로 39℃의 진탕배양기에서 24시간 배양하였다. 이와는 별도로 반추위액만이 포함된 broth medium(blank)을 동일한 조건에서 배양하였다. 탄수화물의 첨가는 blank와 control에 비하여 배양 12시간 이후 배양액(broth medium)의 pH를 낮추었으며 배양 6시간에서는 dextrose 첨가구에서 가장 낮았다(p<0.0001). 배양액 암모니아 농도의 경우 12시간의 배양 이후 탄수화물 첨가구의 pH보다 blank와 control에서 더 증가되었으나(p<0.0111) 첨가한 탄수화물 종류에 따른 뚜렷한 차이는 없었다. 배양 종료시 배양액의 총 VFA 농도는 blank 및 control에 비하여 3종류의 탄수화물 첨가구 모두에서 현저히(p<0.0002) 증가되었다. 또한 배양시간이 경과함에 따라 acetate(C₂)의 조성 비율이 점차 감소되었던 반면 propionate(C₃)의 조성 비율은 점차 증가되었다. 배양 12시간에서는 starch와 cellulose 첨가구에서 C₂의 조성비율이 낮았으나(p<0.0002), 종료시점인 24시간에서는 blank와 control의 경우에 비하여 모든 탄수화물 첨가구에서 더 낮은 것으로 나타났다 (p<0.0001). Propionate의 경우 C₂와는 반대의 경향을 보였다. Butyrate 조성 비율은 24시간에 dextrose와 staph 첨가구에서(p<0.0001) 더 높았다. 한편, 24시간의 배양 후 박테리아 수는 dextrose 첨가구에서 가장 높았으나(p<0.0001) 다른 처리구 간에는 차이가 없었다. Nylon 천에서 배양액으로 유출된 C_(18:1)의 bydrogenation 율(%)은 배양 6시간 및 12시간에서 상대적으로 pH가 낮은 dextrose나 starch 첨가구에서 높았던 반면 cellulose 첨가구에서 낮은 경향을 보였다. 또한 C_(18:1)이나 stearic acid의 형태로 박테리아 lipid로의 incorporation된 율은 탄수화물 첨가구 중 pH가 가장 높았던 cellulose 첨가구에서 11.1%로 가장 증가된 경향이었다. 그러나 hydrogenation 및 incorporation 모두 탄수화물 첨가여부 또는 탄수화물의 종류에 따른 현저한 차이는 없었다. An in vitro study was conducted to examine the effect of carbohydrate sources(dextrose, starch or cellulose) added to the broth medium on fermentation characteristics, bacterial growth, hydrogenation of oleic acid(C_(18:1)) and direct incorporation of C_(18) fatty acids by mined ruminal bacteria in vitro. Carbohydrates were added to 200㎖ non-selective basal broth medium at the level of 0.2%(w/v). Oleic acid(87.4㎎) and 1-^(14)C_(18:1)(2.09uCi) were absorbed into the nylon cloth(2 × 3㎝), and the two pieces of nylon cloth were placed to 200㎖ broth medium for each treatment. Three mls of rumen fluid strained through 8 layers of cheese cloth were added to each broth medium, then was incubated anaerobically in the shaking incubator of 39℃ for 24 hour. The broth media of control which do not contain the carbohydrates and blank which contain rumen fluid only were also incubated. Addition of carbohydrates to the broth medium tended to decrease the pH of broth media after 12h and 24h incubations compared to those of blank and control, and the lowest(p<0.0001) pH was observed from the dextrose addition at the 6h incubation. Ammonia concentrations in the broth media of blank and control after 12h incubation slightly increased(p<0.0111) compared to those in the carbohydrates added media, but there were no differences in pH among carbohydrate sources. Volatile fatty acid concentration in the carbohydrates added broth media increased(p<0.0002) compared to those in blank and control after 24h incubation. As incubation time passed molar proportion of acetate(C₂) decreased gradually but propionate(C₃) proportion increased. Proportions of C₂ were lower (p<0.0002) for the starch and cellulose added media at 12h incubation while increased C₂ proportions were observed from all the carbohydrate added media compared to those from blank and control when the incubation was terminated(24h). Opposite results to the C₂ were observed from C₃. Increased(p<0.0001) molar proportions of butyrate were found from the dextrose and starch added media after 24h incubation. Highest number of viable bacteria was observed from the dextrose added medium after 24h incubation. Percent hydrogenation of C_(18:10) tended to increase for the dextrose and starch added media which were relatively low in pH after 6h and 12h incubation while incorporation(%) of C_(18:1) or C_(18:0) into the bacterial lipids tended to increase for the celluiose addod medium which was high in pH.

DROWSY BEHAVIOR DETECTION BASED ON DRIVING INFORMATION

M. S. WANG,N. T. JEONG,K. S. KIM,S. B. CHOI,S. M. YANG,S. H. YOU,J. H. LEE,서명원 한국자동차공학회 2016 International journal of automotive technology Vol.17 No.1

Drowsy behavior is more likely to occur in sleep-deprived drivers. Individuals’ drowsy behavior detection technology should be developed to prevent drowsiness related crashes. Driving information such as acceleration, steering angle and velocity, and physiological signals of drivers such as electroencephalogram (EEG), and eye tracking are adopted in present drowsy behavior detection technologies. However, it is difficult to measure physiological signal, and eye tracking requires complex experiment equipment. As a result, driving information is adopted for drowsy driving detection. In order to achieve this purpose, driving experiment is performed for obtaining driving information through driving simulator. Moreover, this paper investigates effects of using different input parameter combinations, which is consisted of lateral acceleration, longitudinal acceleration, and steering angles with different time window sizes (i.e. 4 s, 10 s, 20 s, 30 s, 60 s), on drowsy driving detection using random forest algorithm. 20 s-size datasets using parameter combination of accelerations in lateral and longitudinal directions, compared to the other combination cases of driving information such as steering angles combined with lateral and longitudinal acceleration, steering angles only, longitudinal acceleration only, and lateral acceleration only, is considered the most effective information for drivers’ drowsy behavior detection. Moreover, comparing to ANN algorithm, RF algorithm performs better on processing complex input data for drowsy behavior detection. The results, which reveal high accuracy 84.8 % on drowsy driving behavior detection, can be applied on condition of operating real vehicles.

Proteomic Analysis Reveals PGAM1 Altering cis-9, trans-11 Conjugated Linoleic Acid Synthesis in Bovine Mammary Gland.

Wang, T,Lee, S B,Hwang, J H,Lim, J N,Jung, U S,Kim, M J,Kang, H S,Choi, S H,Lee, J S,Roh, S G,Lee, H G American Oil Chemists' Society 2015 Lipids Vol.50 No.5

<P>cis-9, trans-11 Conjugated linoleic acid (CLA) is one of the most extensively studied CLA isomers due to its multiple isomer-specific effects. However, the molecular mechanisms of cis-9,trans-11 CLA synthesis in ruminant mammary gland are still not clearly understood. This process may be mediated, to a certain extent, by trans-11 C18:1 regulated by stearoyl-CoA desaturase-1 (SCD1) and/or its syntrophic proteins. This study aimed to investigate the effects of TVA on SCD1-mediated cis-9,trans-11 CLA synthesis in MAC-T cells and its potential molecular mechanism. Results showed that trans-11 C18:1 was continually taken up and converted into cis-9,trans-11 CLA in MAC-T cells during the 4-h incubation of 50?μM trans-11 C18:1. SCD1 protein expression increased more than twofold at 2?h (P?<?0.01) and 2.5?h (P?<?0.05) before decreasing to less than half of the normal level at 4?h (P?<?0.05). One up-regulated (RAS guanyl releasing protein 4 isoform 1 [RASGRP4]) and six down-regulated proteins (glucosamine-6-phosphate deaminase 1 [GNPDA1], triosephosphate isomerase [TPI1], phosphoglycerate mutase 1 [PGAM1], heat shock protein beta-1 [HSPB1], annexin A3 [ANXA3], thiopurine S-methyltransferase [TPMT]) were found in MAC-T cells treated with trans-11 C18:1. Of these seven identified proteins, the presence of GNPDA1 and PGAM1 was verified in several models. More trans-11 C18:1 was taken up after PGAM1 knockdown by small interfering RNA (siRNA). In conclusion, our data suggested that PGAM1 may have a negative relationship with SCD1 and seemed to be involved in cis-9, trans-11 CLA synthesis by facilitating the absorption of trans-11 C18:1 in the bovine mammary gland.</P>

Structural Changes in the Oxygen-Evolving Complex of Photosystem II Induced by the S ₁ to S ₂ Transition: A Combined XRD and QM/MM Study

Askerka, Mikhail,Wang, Jimin,Brudvig, Gary W.,Batista, Victor S. American Chemical Society 2014 Biochemistry Vol.53 No.44

<P/><P>The S<SUB>1</SUB> → S<SUB>2</SUB> transition of the oxygen-evolving complex (OEC) of photosystem II does not involve the transfer of a proton to the lumen and occurs at cryogenic temperatures. Therefore, it is commonly thought to involve only Mn oxidation without any significant change in the structure of the OEC. Here, we analyze structural changes upon the S<SUB>1</SUB> → S<SUB>2</SUB> transition, as revealed by quantum mechanics/molecular mechanics methods and the isomorphous difference Fourier method applied to serial femtosecond X-ray diffraction data. We find that the main structural change in the OEC is in the position of the dangling Mn and its coordination environment.</P>

Evaluation of Sulfur and Multi-Walled Carbon Nanotube Composite Synthesized by Dissolution and Precipitation for Li/S Batteries

Park, J. S.,Kim, D. J.,Park, J. W.,Ryu, H. S.,Kim, K. W.,Wang, G. X.,Ahn, H. J. American Scientific Publishers 2012 Journal of Nanoscience and Nanotechnology Vol.12 No.7

<P>An elemental sulfur and multi-walled carbon nanotube (S-MWNT) composite was synthesized by dissolving sulfur in ammonium sulfides and then precipitating on MWNT. Morphology observation by scanning electron microscopy (SEM) confirmed that S-MWNT product was successfully prepared by incorporating sulfur into MWNT network. Without additional conducting material, the S-MWNT composite cathodes were prepared for electrochemical tests. The properties measured in discharge-charge cycling test showed that the composite had the initial discharge capacity of 1024 mAh g(-1), which is about 61% sulfur utilization. However, in the subsequent cycling, the capacities faded. To determine the reason of rapid capacity drop, S-MWNT composite cathodes were compared in the cycling tests with varying three kinds of electrolytes and the cathode was subjected to physical force by rolling. The changes in the cycle performances proved that the deterioration of S-MWNT composite cathodes was not related to the electrolytes but to physical bonding that may not maintain the conducting path between sulfur and MWNT.</P>

Bendable and flexible supercapacitor based on polypyrrole-coated bacterial cellulose core-shell composite network

Wang, F.,Kim, H.J.,Park, S.,Kee, C.D.,Kim, S.J.,Oh, I.K. Elsevier Applied Science Publishers 2016 Composites science and technology Vol.128 No.-

We report a bendable and flexible supercapacitor based on polypyrrole-coated core-shell bacterial cellulose composite networks. As an initial step, gel-type bacterial cellulose was transformed into individually ultrathin bacterial cellulose nanofibers (TOBC) with diameters of 3-5 nm, by using 2,2,6,6-tetramethylpylperidine-l-oxyl radical (TEMPO)-mediated oxidation and successive mild disintegration in water. And, PPy-TOBC core-shell nanofiber network electrodes were synthesized in situ by oxidative polymerization of pyrrole with iron (III) chloride on the TOBC nanofibers in aqueous medium. The PPy-TOBC core-shell nanofiber network electrode exhibited a high porosity (101 m<SUP>2</SUP>/g) and high conductivity (~6.63 S/cm) due to the homogenous coating of PPy nanoparticles on the TOBC nanofiber network. The as-prepared PPy-TOBC supercapacitor cell, fabricated with PVDF-EMIMBF<SUB>4</SUB> (1-Ethyl-3-methylimidazolium tetrafluoroborate) polymer electrolyte, showed a specific capacitance of 153 F/g and energy density of 21.22 Wh/kg at the current density of 0.2 A/g. Moreover, the PPy-TOBC supercapacitor exhibited an exceptionally good cyclic stability with ~93% capacitance retention after 100 cycles; it also showed good bending stability due to the mechanical failure tolerance of the nanofiber-networked electrodes. The present approach is a versatile, inexpensive, and promising way to develop the cellulose-based nanofiber network electrodes for practical energy storage applications.

Cloning of Chicken Microsomal Glutathione S-transferase 1 Gene (MGST1) and Identification of Its Different Splice Variants

Wang, X.-T.,Zhang, H.,Zhao, C.-J.,Li, J.-Y.,Xu, G.-Y.,Lian, L.-S.,Wu, C.-X.,Deng, Xuemei Asian Australasian Association of Animal Productio 2009 Animal Bioscience Vol.22 No.2

Mammal microsomal glutathione transferase 1 (MGST1) can conjugate many toxic or carcinogenic substances and depress oxidative stress. In this study, Chicken MGST1 and its variants were cloned for the first time and were composed of 956 or 944 nucleotides. The 12 nt deletion in the exon 2 did not alter the GT-AG rule and the ORFs for the two MGST1 variants were the same, which both comprised 465 nucletides and encoded a peptide with 155 amino acids. It was found that the two different splice variants identified using RT-PCR expressed in all three organs investigated of Dwarf Brown Chicken, namely liver, spleen and shell gland. Moreover, the expression level of MGST1 mRNA in the liver of Dwarf Brown chickens was the highest (p<0.01), and there were no significant differences between the spleen and the shell gland. These results provide a base for studying the biological function of Chicken MGST1.

The Expression of Porcine Adiponectin and Stearoyl Coenzyme a Desaturase Genes in Differentiating Adipocytes

Wang, P.H.,Ko, Y.H.,Liu, B.H.,Peng, H.M.,Lee, M.Y.,Chen, C.Y.,Li, Y.C.,Ding, S.T. Asian Australasian Association of Animal Productio 2004 Animal Bioscience Vol.17 No.5

The gene expression of porcine adiponectin and stearoyl coenzyme A desaturase (SCD) was investigated in this study. The partial gene sequences for adiponectin and SCD were amplified by RT-PCR from subcutaneous adipose tissue and cloned by TA cloning techniques. Sequences of these genes were determined and found to be highly homologous to that of other species, suggesting similar function of these genes as in other species. The transcripts of these adipocyte-related genes in pig tissues were measured by Northern analysis. The transcripts for adiponectin and SCD were highly expressed in porcine subcutaneous adipose tissue; the transcripts for SCD were also barely detected in the liver, but the greatest concentrations were in the adipose tissue. In porcine stromalvascular cells (S/V cells) cultured in vitro, transcripts for adiponectin and SCD increased gradually during adipocyte differentiation. The level of adipocyte adiponectin mRNA was associated with late adipocyte differentiation, indicating the gene may not be involved in adipocyte differentiation but has great importance in porcine adipocyte functions. The SCD transcripts were not detectable until 2 d after induction of adipocyte differentiation. It was highly expressed in differentiating porcine adipocytes (2 to 10 d after the induction of adipocyte differentiation), indicating a significant role of SCD in adipocytes.

Semisupervised Tripled Dictionary Learning for Standard-Dose PET Image Prediction Using Low-Dose PET and Multimodal MRI

Wang, Yan,Shen, Dinggang,Ma, Guangkai,An, Le,Shi, Feng,Zhang, Pei,Lalush, David S.,Wu, Xi,Pu, Yifei,Zhou, Jiliu IEEE 2017 IEEE Transactions on Biomedical Engineering Vol.64 No.3

<P>Objective: To obtain high-quality positron emission tomography (PET) image with low-dose tracer injection, this study attempts to predict the standard-dose PET (S-PET) image from both its low-dose PET (L-PET) counterpart and corresponding magnetic resonance imaging (MRI). Methods: It was achieved by patch-based sparse representation (SR), using the training samples with a complete set of MRI, L-PET and S-PET modalities for dictionary construction. However, the number of training samples with complete modalities is often limited. In practice, many samples generally have incomplete modalities (i.e., with one or two missing modalities) that thus cannot be used in the prediction process. In light of this, we develop a semisupervised tripled dictionary learning (SSTDL) method for S-PET image prediction, which can utilize not only the samples with complete modalities (called complete samples) but also the samples with incomplete modalities (called incomplete samples), to take advantage of the large number of available training samples and thus further improve the prediction performance. Results: Validation was done on a real human brain dataset consisting of 18 subjects, and the results show that our method is superior to the SR and other baseline methods. Conclusion: This paper proposed a new S-PET prediction method, which can significantly improve the PET image quality with low-dose injection. Significance: The proposed method is favorable in clinical application since it can decrease the potential radiation risk for patients.</P>