Experimental research and molecular dynamics simulation on thermal properties of capric acid/ethylene-vinyl/graphene composite phase change materials

Yue Gu,Linhua Jiang,Weizhun Jin,Zhenhua Wei,Xing Liu,Mingzhi Guo,Kailun Xia,Lei Chen 한국공업화학회 2021 Journal of Industrial and Engineering Chemistry Vol.99 No.-

In this paper, a new series of phase change materials (PCMs) composed of capric acid/ethylene-vinylacetate/graphene (CA/EVA/GR) were prepared and thermal properties were investigated using moleculardynamics simulation. The composite PCMs were characterized by Fourier transform infraredspectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), differential scanningcalorimetry (DSC) and thermal conductivity measurement. FT-IR, XRD and SEM results manifest that CAcan be successfully wrapped by EVA and GR additives, and there is no chemical reaction between CA, EVAand GR. DSC results indicate that adding GR into CA/EVA can result in composite PCMs maintain the highlatent heat, while too much GR will cause a significant reduction in latent heat. Thermal conductivityobtained from experimental tests reveal that GR can gradually enhance the thermal conductivity of CA/EVA with increasing dosage of GR. The experimental results of thermal conductivity fall close to that ofmolecular dynamics (MD) simulation at GR dosages below 1.8 wt%, but the experimental results present atrend which is contrary to MD simulation at higher GR dosages. The mean square displacement (MSD)results manifest that composite PCMs containing 1.8 wt% GR has the highest diffusion coefficient, whilehigher GR dosage will reduce the diffusion coefficient gradually.

An Improved K-means Algorithm based on Mapreduce and Grid

Li Ma,Lei Gu,Bo Li,Yue Ma,Jin Wang 보안공학연구지원센터 2015 International Journal of Grid and Distributed Comp Vol.8 No.1

The traditional K-means clustering algorithm is difficult to initialize the number of clusters K, and the initial cluster centers are selected randomly, this makes the clustering results very unstable. Meanwhile, algorithms are susceptible to noise points. To solve the problems, the traditional K-means algorithm is improved. The improved method is divided into the same grid in space, according to the size of the data point property value and assigns it to the corresponding grid. And count the number of data points in each grid. Selecting M(M>K) grids, comprising the maximum number of data points, and calculate the central point. These M central points as input data, and then to determine the k value based on the clustering results. In the M points, find K points farthest from each other and those K center points as the initial cluster center of K-means clustering algorithm. At the same time, the maximum value in M must be included in K. If the number of data in the grid less than the threshold, then these points will be considered as noise points and be removed. In order to make the improved algorithm can adapt to handle large data. We will parallel the improved k-mean algorithm and combined with the MapReduce framework. Theoretical analysis and experimental results show that the improved algorithm compared to the traditional K-means clustering algorithm has high quality results, less iteration and has good stability. Parallelized algorithm has a very high efficiency in data processing, and has good scalability and speedup.

Experimental studies of suppressing effectiveness on sloshing with two perforated floating plates

Yue-Min Yu,Ning Ma,She-Ming Fan,Xie-Chong Gu 대한조선학회 2019 International Journal of Naval Architecture and Oc Vol.11 No.1

In the present paper, model tests of suppressing sloshing fitted with two perforated floating plates are carried out. The study involves identification of system performance such as the suppression and the solidity ratio. Three different solidity ratios of perforated plates have been tried out as potential positive slosh damping devices. A series of painstaking experiments have been conducted in a rigid rectangular tank on six degrees of freedom motion platform under roll harmonic excitation. Comparison of the clean tank shows that the three types of perforated plates are all effective on damping the run-up and impact pressure along the bulkhead. The parametric study indicates that the perforated plate with the median solidity ratio is the most optimal one in suppressing sloshing among three configurations.

Heterologous expression of Solanum tuberosum NAC1 gene confers enhanced tolerance to salt stress in transgenic Nicotiana benthamiana

Yue Lu,Zhuang Yong,Gu Yuanyang,Li Hui,Tu Shengbin,Yang Xiaocheng,Huang Weizao 한국식물학회 2021 Journal of Plant Biology Vol.64 No.6

The plant-specific transcription factors NACs (NAM, ATAF1, 2, CUC), one major transcription factor family, play significant roles in various physiological processes including abiotic stresses. In our study, an NAC gene from potato (Solanum tuberosum L.) was cloned and named as StNAC1 for a high-sequence similarity to SlNAC1, a well-known tomato NAC gene regulating multiple stress responses and fruit ripening. StNAC1 gene was significantly induced under salt stress. Then, we constructed StNAC1-overexpressing transgenic Nicotiana benthamiana plants and obtained three homozygous transgenic lines. The phenotypic analysis results showed that StNAC1-overexpressing transgenic plants had not only higher seed germination and green leaf rates, but also accumulated less ROS and more proline than wide-type plants under salt stress, which resulted in improving transgenic plants salt tolerance. These suggested that StNAC1 gene might function as a positive regulator in plant response to salt stress.

Inhibition of acetylation of histones 3 and 4 attenuates aortic valve calcification

Jia Gu,Yan Lu,Menqing Deng,Ming Qiu,Yunfan Tian,Yue Ji,Pengyu Zong,Yongfeng Shao,Rui Zheng,Bin Zhou,Xiangqing Kong,Wei Sun 생화학분자생물학회 2019 Experimental and molecular medicine Vol.51 No.-

Aortic valve calcification develops in patients with chronic kidney disease who have calcium and phosphate metabolic disorders and poor prognoses. There is no effective treatment except valve replacement. However, metabolic disorders put patients at high risk for surgery. Increased acetylation of histones 3 and 4 is present in interstitial cells from human calcific aortic valves, but whether it is involved in aortic valve calcification has not been studied. In this study, we found that treating cultured porcine aortic valve interstitial cells with a high-calcium/high-phosphate medium induced calcium deposition, apoptosis, and expression of osteogenic marker genes, producing a phenotype resembling valve calcification in vivo. These phenotypic changes were attenuated by the histone acetyltransferase inhibitor C646. C646 treatment increased the levels of class I histone deacetylase members and decreased the acetylation of histones 3 and 4 induced by the high-calcium/high-phosphate treatment. Conversely, the histone deacetylase inhibitor suberoylanilide hydroxamic acid promoted valve interstitial cell calcification. In a mouse model of aortic valve calcification induced by adenine and vitamin D treatment, the levels of acetylated histones 3 and 4 were increased in the calcified aortic valves. Treatment of the models with C646 attenuated aortic valve calcification by restoring the levels of acetylated histones 3 and 4. These observations suggest that increased acetylation of histones 3 and 4 is part of the pathogenesis of aortic valve calcification associated with calcium and phosphate metabolic disorders. Targeting acetylated histones 3 and 4 may be a potential therapy for inoperable aortic valve calcification in chronic kidney disease patients.

The Inhibitory Effects of Cu(2+) on Exopalaemon carinicauda Arginine Kinase via Inhibition Kinetics and Molecular Dynamics Simulations.

Si, Yue-Xiu,Lee, Jinhyuk,Yin, Shang-Jun,Gu, Xiao-Xu,Park, Yong-Doo,Qian, Guo-Ying Humana Press 2015 Applied biochemistry and biotechnology Vol.176 No.4

<P>We studied the Cu2+-mediated inhibition and aggregation of Exopalaemon carinicauda arginine kinase ( ECAK). We found that Cu2+ significantly inactivated ECAK activity and double-reciprocal kinetics demonstrated that Cu2+ induced noncompetitive inhibition of arginine and ATP ( IC50=2.27 +/- 0.16 mu M; K-i for arginine=13.53 +/- 3.76; K-i for ATP=4.02 +/- 0.56). Spectrofluorometry results showed that Cu2+ induced ECAK tertiary structural changes including the exposure of hydrophobic surfaces that directly induced ECAK aggregation. The addition of osmolytes such as glycine and proline successfully blocked ECAK aggregation induced by Cu2+ and recovered ECAK activity. We built a 3D structure for ECAK using the ECAK ORF gene sequence. Molecular dynamics ( MD) and docking simulations between ECAK and Cu2+ were conducted to elucidate the binding mechanisms. The results showed that Cu2+ blocked the entrance to the ATP active site; these results are consistent with the experimental result that Cu2+ induced ECAK inactivation. Since arginine kinase ( AK) plays an important role in cellular energy metabolism in invertebrates, our study can provide new information about the effect of Cu2+ on ECAK enzymatic function and unfolding, including aggregation, and the protective effects of osmolytes on ECAK folding to better understand the role of the invertebrate ECAK metabolic enzyme in marine environments.</P>

Serial Frozen Fecal Microbiota Transplantation in the Treatment of Chronic Intestinal Pseudo-obstruction: A Preliminary Study

( Lili Gu ),( Chao Ding ),( Hongliang Tian ),( Bo Yang ),( Xuelei Zhang ),( Yue Hua ),( Yifan Zhu ),( Jianfeng Gong ),( Weiming Zhu ),( Jieshou Li ),( Ning Li ) 대한소화기기능성질환·운동학회(구 대한소화관운동학회) 2017 Journal of Neurogastroenterology and Motility (JNM Vol.23 No.2

Background/Aims Chronic intestinal pseudo-obstruction (CIPO) is a serious, life-threatening motility disorder that is often related to bacterial overgrowth. Fecal microbiota transplantation (FMT) results in restoration of the normal intestinal microbial community structure. We investigated the efficacy of FMT in the treatment of CIPO patients. Methods Nine patients (age 18-53 years) with CIPO were enrolled in this prospective, open-label study. Patients received FMT for 6 consecutive days through nasojejunal (NJ) tubes and were followed up for 8 weeks after treatment. We evaluated the rate of clinical improvement and remission, feeding tolerance of enteral nutrition, and CT imaging scores of intestinal obstructions. Lactulose hydrogen breath tests were performed before FMT and 8 weeks after FMT to evaluate for the presence small intestinal bacterial overgrowth (SIBO). Results FMT significantly alleviated bloating symptoms, and symptoms of pain were relieved 2 weeks after FMT. Enteral nutrition administered through a NJ tube after FMT was well-tolerated by 66.7% (6/9) of patients. CT scores of intestinal obstructions were significantly reduced after FMT (P = 0.014). SIBO was eliminated in 71.0% (5/7) of patients. Conclusions This pilot study demonstrated the safety of using FMT. FMT may relieve symptoms in selected patients with CIPO. FMT may also improve patient tolerance of enteral nutrition delivered via a NJ tube. (J Neurogastroenterol Motil 2017;23:289-297)

Making of Free View point 3D Images Using One Camera

Fei Gu,Takayuki Nakata,Yue Bao 제어로봇시스템학회 2009 제어로봇시스템학회 국제학술대회 논문집 Vol.2009 No.8

In recent years, it is necessary to show the sight of a remote place as a picture. In this case, to get an abundant amount of information. As the conventional technique, There were method which use two or more cameras to take photographs, and an ther method which use several photographs to generate a middle view point. However, the former, It tends to become an expensive and complicated system, and is the latter, there is a problem that information is missing with occlusion. In this paper, we propose a system which use done camera and a spin mirror to generate the free view point 3D image. This system used a method which called a light processing algorithm to make the free view point 3D image from the obtained photography picture. There liability of the proposed method is discussed with experimental result.

Preparation and properties of the green-emitting phosphors NaCa0.98-xMgxPO4:

Bo Yue,Juan Gu,Guangfu Yin,Zhongbing Huang,Xiaoming Liao,Yadong Yao,Yunqing Kang,Panli You 한국물리학회 2010 Current Applied Physics Vol.10 No.4

In this study, a series of the green-emitting phosphors NaCa0.98-xMgxPO4:Eu2þ 0:02 was prepared through high temperature solid-state reaction. The structure and spectroscopic properties of these samples were characterized by XRD, FT-IR, reflectance spectra and photoluminescence (PL) spectra, respectively. The effect of Mg2+ co-doping concentration on the PL intensity of as-prepared samples was also investigated. The enhanced intensities of excitation and emission band of Eu2+ and a slight red-shift of the emission peak were observed due to Mg2+ co-doping. When the x value is 0.08, the phosphors possessed the maximum emission intensity monitored at 360 nm and the emission spectrum shows a single band centered at about 500 nm. The obtained phosphors had strong absorption in near-UV zone (350–400 nm), which can match the emission of near-UV light-emitting diodes. The prepared material is potential green phosphors for white LEDs.

Pig Large tumor suppressor2 (Lats2), a novel gene that may regulate the fat reduction in adipocyte

( Qiu Yue Liu ),( Xiao Rong Gu ),( Yi Qiang Zhao ),( Jin Zhang ),( Yao Feng Zhao ),( Qing Yong Meng ),( Guo Heng Xu ),( Xiao Xiang Hu ),( Ning Li ) 생화학분자생물학회 2010 BMB Reports Vol.43 No.2