Mass Spectrometry for Metabolome Analysis

Wang, Xiaohang,Li, Liang Korean Society for Mass Spectrometry 2020 Mass spectrometry letters Vol.11 No.2

Metabolomics has become an important research field with many areas of applications ranging from disease biomarker discovery to global biology systems study. A key step in metabolomics is to perform metabolome analysis to obtain quantitative information on metabolic changes among comparative samples. Mass spectrometry (MS) is widely used for highly sensitive detection of many different types of metabolites. In this review, we highlight some of the more commonly used MS techniques for metabolome analysis.

Biexponential Apparent Diffusion Coefficients Values in the Prostate: Comparison among Normal Tissue, Prostate Cancer, Benign Prostatic Hyperplasia and Prostatitis

Xiaohang Liu,Weijun Peng,Liangping Zhou,He Wang 대한영상의학회 2013 Korean Journal of Radiology Vol.14 No.2

Objective: To investigate the biexponential apparent diffusion parameters of diverse prostate tissues and compare them with monoexponential apparent diffusion coefficient (ADC) value in the efficacy to discriminate prostate cancer from benign lesions. Materials and Methods: Eleven healthy volunteers and 61 patients underwent a conventional (b-factors 0, 1000 s/mm2) and a 10 b-factor (0 to 3000 s/mm2) diffusion-weighted imaging (DWI). The monoexponential ADC value and biexponential parameters of fast ADC (ADCf), fraction of ADCf (f), slow ADC (ADCs) value for 29 prostate cancer, 28 benign prostatic hyperplasia (BPH), 24 prostatitis lesions and normal tissue were calculated and compared. Receiver operating characteristic analysis was performed to determine the sensitivity, specificity and optimal cut-off points. Results: Prostate cancer had lower ADC, ADCf, f, and ADCs than all other tissues (p < 0.01). Prostatitis exhibited a lower ADC, ADCf, ADCs and f than the peripheral zone tissue (p < 0.01), and BPH showed a lower ADC and ADCf than the central gland tissue (p < 0.01). The ADCf demonstrated a comparable accuracy with ADC in differentiating cancer from BPH [area under the curve (AUC) 0.93 vs. 0.92] and prostatitis AUC 0.98 vs. 0.99) (both p > 0.05), but the AUC of f and ADCs in differentiating cancer from BPH (0.73 and 0.81) and prostatitis (0.88 and 0.91) were significantly lower than ADC (all p < 0.05). Conclusion: The biexponential DWI appears to provide additional parameters for tissue characterization in prostate, and ADCf helps to yield comparable accuracy with ADC in differentiating cancer from benign lesions.

Biochemical Properties of Fish Sauce Prepared Using Low Salt, Solid State Fermentation with Anchovy By-products

Xiaohang Yu,Xiangzhao Mao,Shuai He,Pei Liu,Yanchao Wang,Changhu Xue 한국식품과학회 2014 Food Science and Biotechnology Vol.23 No.5

Biochemical characteristics of fast fermentedfish sauce made by adding anchovy juice during the processof low salt, solid state fermentation were investigated using3 different techniques (A: adding anchovy juice in theprocess of making koji, B: adding anchovy juice in theprocess of fermentation, and C: not adding anchovy juice). After fermentation under optimized conditions, the aminonitrogen contents of sauces A and B were 7.50 and 7.73mg/mL after two weeks, respectively. Chemical analysissuggested that the amounts of amino nitrogen and reducingsugar, degree of hydrolysis (DH), DPPH radical-scavengingactivity, total acidity, and total amino acid in sauce B werehigher than those in sauce A. Volatile odorant analysis andsensory evaluation showed that sauce B was superior tosauce A. Adding anchovy juice during the process offermentation is a good way to produce a fish sauce with agood flavor and nutrition value.

Synthesis of Composite Carbon-Based Nano-Zero-Valent Iron Micro-Electrolytic Material and Removal of Dichloromethanesulfonic Acid in Drinking Water

Kai Liu,Xiaohang Zhang,Hao Wang,Xuwen He,Zhonghua Shangguan,Yali Shi,Shipeng Yang 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2019 NANO Vol.14 No.5

Composite carbon-based nano-zero-valent iron materials not only have excellent characteristics of nano materials, but also solve the difficulty of recycling nano materials after use, and overcome the shortcomings of the nano materials. The introduction of copper increases the redox reaction activity of the micro-electrolytic material and expands the applicable pH range of the reaction environment. In the range of pH = 3–9, the removal efficiency of dichloromethanesulfonic acid (Cl2-MSA) was maintained at 95.5–99.7% after 30 min. Continuous dynamic simulation experiments verified that the composite carbon-based nano zero-valent iron material has a stable removal effect on the target pollutants.

Systematic Band Gap Tuning of BaSnO₃ via Chemical Substitutions: The Role of Clustering in Mixed-Valence Perovskites

Lee, Seunghun,Wang, Haihang,Gopal, Priya,Shin, Jongmoon,Jaim, H. M. Iftekhar,Zhang, Xiaohang,Jeong, Se-Young,Usanmaz, Demet,Curtarolo, Stefano,Fornari, Marco,Buongiorno Nardelli, Marco,Takeuchi, Ichir American Chemical Society 2017 Chemistry of materials Vol.29 No.21

<P>By combining high-throughput experiments and first-principles calculations based on the DFT-ACBN0 approach, we have investigated the energy band gap of Sr-, Pb-, and Bi-substituted BaSnO<SUB>3</SUB> over wide concentration ranges. We show that the band gap energy can be tuned from 3 to 4 eV by chemical substitution. Our work indicates the importance of considering the mixed-valence nature and clustering effects upon substitution of BaSnO<SUB>3</SUB> with Pb and Bi. Starting from the band gap of ∼3.4 eV for pure BaSnO<SUB>3</SUB>, we find that Pb substitution changes the gap in a nonmonotonic fashion, reducing it by as much as 0.3 eV. Bi substitution provides a monotonic reduction but introduces electronic states into the energy gap due to Bi clustering. Our findings provide new insight into the ubiquitous phenomena of chemical substitutions in perovskite semiconductors with mixed-valence cations that underpin their physical properties.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/cmatex/2017/cmatex.2017.29.issue-21/acs.chemmater.7b03381/production/images/medium/cm-2017-03381d_0005.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/cm7b03381'>ACS Electronic Supporting Info</A></P>

Effects of HY addition on NiMoS active phase of NiMo(NH3) impregnated NiMo/Al2O3-HY and its role in 4,6-dimethyl-dibenzothiophene hydrodesulfurization

Yanzeng Dong,Xiaohang Yu,Zhiheng Wang,Xin Liu,Yanyan Liu,Ruiyao Gao,Songdong Yao 한국공업화학회 2023 Journal of Industrial and Engineering Chemistry Vol.117 No.-

Effects of HY addition on NiMoS active phase of NiMo(NH3) impregnated NiMo/Al2O3-HY and its role in4,6-dimethyl-dibenzothiophene hydrodesulfurization was investigated. The results show that HY canpromote HDS reaction by changing the morphology of NiMoS nanoclusters even when isomerization of4,6-DMDBT is not involved. In the absence of strong acid sites, TOF of NiMo/Al2O3 catalyst was stillimproved by 90%. XRD, H2-TPR, Raman, TEM, and XPS characterization show that proper metal supportinteraction caused by HY addition is beneficial to the formation of large-scale multilayer NiNoS clusters,the enrichment of Ni in NiMoS clusters and the increase of NiMoS active sites, thereby leading HDS catalystexhibiting highest intrinsic activity (TOF). However, too strong or too weak metal support interactionwill reduce intrinsic activity for HDS catalysts. When pH value of impregnation solution is 10, thestrong metal support interaction reduces layer numbers of NiMoS clusters. When pH value of impregnationsolution is 11, negative charge hinders the formation of NiMoS clusters. This not only leads to a furtherdecrease HYD pathway selectivity, but also significantly reduces the initial reaction rate of HDScatalyst.

Multi-scale and Interactive Visual Analysis of Public Bicycle System

( Xiaoying Shi ),( Yang Wang ),( Fanshun Lv ),( Xiaohang Yang ),( Qiming Fang ),( Li Zhang ) 한국인터넷정보학회 2019 KSII Transactions on Internet and Information Syst Vol.13 No.6

Public bicycle system (PBS) is a new emerging and popular mode of public transportation. PBS data can be adopted to analyze human movement patterns. Previous work usually focused on specific scales, and the relationships between different levels of hierarchies are ignored. In this paper, we introduce a multi-scale and interactive visual analytics system to investigate human cycling movement and PBS usage condition. The system supports level-of-detail explorative analysis of spatio-temporal characteristics in PBS. Visual views are designed from global, regional and microcosmic scales. For the regional scale, a bicycle network is constructed to model PBS data, and an flow-based community detection algorithm is applied on the bicycle network to determine station clusters. In contrast to the previous used Louvain algorithm, our method avoids producing super-communities and generates better results. We provide two cases to demonstrate how our system can help analysts explore the overall cycling condition in the city and spatio-temporal aggregation of stations.

Enabling Context-aware Smart Home with Semantic Web Technologies

Daqing Zhang,Tao Gu,Xiaohang Wang 한국과학기술원 인간친화 복지 로봇 시스템 연구센터 2005 International Journal of Assistive Robotics and Me Vol.6 No.4

  Context-awareness has emerged as a key enabling technology for future smart homes. In this paper, we propose a generic layered model (the Context Stack) to guide the context-aware system design. We investigate the use of Semantic Web technologies in context modeling and reasoning. A Web Ontology based context model (CONON) is defined to facilitate explicit context representation, semantic context sharing, and logic reasoning. We show how the use of logic reasoning enables context-aware services to deduce high-level, implicit context from low-level, explicit context. In particular, we integrate the temporal ontology into our ontology model to facilitate annotating and reasoning about temporal context information. Following the general layered model, we present an OSGi-based context-aware service architecture for smart homes. We also build the smart home prototype with context-aware services.

Advanced Small-Signal Model of Multi-Terminal Modular Multilevel Converters for Power Systems Based on Dynamic Phasors

Pan Hu,Hongkun Chen,Lei Chen,Xiaohang Zhu,Xuechun Wang 전력전자학회 2018 JOURNAL OF POWER ELECTRONICS Vol.18 No.2

Modular multilevel converter (MMC)-based high-voltage direct current (HVDC) presents attractive technical advantages and contributes to enhanced system operation and reduced oscillation damping in dynamic MMC–HVDC systems. We propose an advanced small-signal multi-terminal MMC–HVDC based on dynamic phasors and state space for power system stability analysis to enhance computational accuracy and reduce simulation time. In accordance with active and passive network control strategies for multi-terminal MMC–HVDC, the matchable small-signal stability models containing high harmonics and dynamics of internal variables are conducted, and a related theoretical derivation is carried out. The proposed advanced small-signal model is then compared with electromagnetic–transient and traditional small-signal state-space models by adopting a typical multi-terminal MMC–HVDC network with offshore wind generation. Simulation indicates that the advanced small-signal model can successfully follow the electromechanical transient response with small errors and can predict the damped oscillations. The validity and applicability of the proposed model are effectively confirmed.

Advanced Small-Signal Model of Multi-Terminal Modular Multilevel Converters for Power Systems Based on Dynamic Phasors

Hu, Pan,Chen, Hongkun,Chen, Lei,Zhu, Xiaohang,Wang, Xuechun The Korean Institute of Power Electronics 2018 JOURNAL OF POWER ELECTRONICS Vol.18 No.2

Modular multilevel converter (MMC)-based high-voltage direct current (HVDC) presents attractive technical advantages and contributes to enhanced system operation and reduced oscillation damping in dynamic MMC-HVDC systems. We propose an advanced small-signal multi-terminal MMC-HVDC based on dynamic phasors and state space for power system stability analysis to enhance computational accuracy and reduce simulation time. In accordance with active and passive network control strategies for multi-terminal MMC-HVDC, the matchable small-signal stability models containing high harmonics and dynamics of internal variables are conducted, and a related theoretical derivation is carried out. The proposed advanced small-signal model is then compared with electromagnetic-transient and traditional small-signal state-space models by adopting a typical multi-terminal MMC-HVDC network with offshore wind generation. Simulation indicates that the advanced small-signal model can successfully follow the electromechanical transient response with small errors and can predict the damped oscillations. The validity and applicability of the proposed model are effectively confirmed.