Lipopolysaccharides Trigger Two Successive Bursts of Reactive Oxygen Species at Distinct Cellular Locations

Shang-Guan, Keke,Wang, Min,Htwe, Nang Myint Phyu Sin,Li, Ping,Li, Yaoshen,Qi, Fan,Zhang, Dawei,Cao, Min,Kim, Chanhong,Weng, Haiyong,Cen, Haiyan,Black, Ian M.,Azadi, Parastoo,Carlson, Russell W.,Stacey American Society of Plant Biologists 2018 Plant Physiology Vol.176 No.3

<P>Lipopolysaccharides induce a long-lasting burst of reactive oxygen species that is largely associated with chloroplasts.</P><P>Lipopolysaccharides (LPS) are major components of the outer membrane of gram-negative bacteria and are an important microbe-associated molecular pattern (MAMP) that triggers immune responses in plants and animals. A previous genetic screen in Arabidopsis (<I>Arabidopsis thaliana</I>) identified LIPOOLIGOSACCHARIDE-SPECIFIC REDUCED ELICITATION (LORE), a B-type lectin <I>S</I>-domain receptor kinase, as a sensor of LPS. However, the LPS-activated LORE signaling pathway and associated immune responses remain largely unknown. In this study, we found that LPS trigger biphasic production of reactive oxygen species (ROS) in Arabidopsis. The first transient ROS burst was similar to that induced by another MAMP, flagellin, whereas the second long-lasting burst was induced only by LPS. The LPS-triggered second ROS burst was found to be conserved in a variety of plant species. Microscopic observation of the generation of ROS revealed that the LPS-triggered second ROS burst was largely associated with chloroplasts, and functional chloroplasts were indispensable for this response. The lipid A moiety, the most conserved portion of LPS, appears to be responsible for the second ROS burst. Surprisingly, the LPS- and lipid A-triggered second ROS burst was only partially dependent on LORE. Together, our findings provide insight on the LPS-triggered ROS production and the associated signaling pathway.</P>

Magnetite-based Biochar Coupled with Binary Oxidants for the Effective Removal of Mixed Dye from Wastewater

Mingxia Yu,Huosheng Li,Keke Li,Yuting Li,Fengli Liu,Gaosheng Zhang,Tangfu Xiao,Ping Zhang,Hongguo Zhang,Jianyou Long 한국섬유공학회 2022 Fibers and polymers Vol.23 No.2

Decolorization and organic degradation of wastewater containing multiple dyes are still challenging inwastewater treatment. Magnetic biochar coupled with advanced oxidation is a potential solution to this issue. In this study,a series of magnetite-based biochar composites (Fe3O4@C) was prepared and compared for the removal of mixed dyes,including methyl orange (MO), rhodamine B (RhB), methylene blue (MB), and an organic macromolecule, humic acid(HA). The pyrolysis of watermelon rinds followed by precipitation of Fe3O4 onto the biochar was selected as the optimummethod to prepare an adsorbent and catalyst to couple binary oxidants (hypochlorite and persulfate) for color and totalorganic carbon removal. Persulfate was prone to degrade HA and MB, while hypochlorite was inclined to oxidize MO andRhB. Fe3O4@C exhibited better dye removal performance in coupling with binary oxidants than with a single oxidant. Formixed dye solutions with an initial concentration of 50 mg/l for each dye, the highest TOC (57.24±3.17 %) and the colorremoval efficiencies (94.13±1.68 %) for the mixed dye solution were achieved at a sorbent dosage of 1 g/l and an oxidantdosage of 5 mmol/l for both hypochlorite and persulfate. Multiple free radicals, including hydroxyl radicals, sulfateradicals, and hypochlorite-induced radicals, play critical roles in the degradation of mixed dyes and color removal. Theregeneratibility and reutilization of the magnetic Fe3O4@C composite were effective and stable. The results obtained inthis study show that the combined Fe3O4@C and binary oxidants technique is promising for the treatment of multi-dyewastewater.

Privacy measurement method using a graph structure on online social networks

Li, XueFeng,Zhao, Chensu,Tian, Keke Electronics and Telecommunications Research Instit 2021 ETRI Journal Vol.43 No.5

Recently, with an increase in Internet usage, users of online social networks (OSNs) have increased. Consequently, privacy leakage has become more serious. However, few studies have investigated the difference between privacy and actual behaviors. In particular, users' desire to change their privacy status is not supported by their privacy literacy. Presenting an accurate measurement of users' privacy status can cultivate the privacy literacy of users. However, the highly interactive nature of interpersonal communication on OSNs has promoted privacy to be viewed as a communal issue. As a large number of redundant users on social networks are unrelated to the user's privacy, existing algorithms are no longer applicable. To solve this problem, we propose a structural similarity measurement method suitable for the characteristics of social networks. The proposed method excludes redundant users and combines the attribute information to measure the privacy status of users. Using this approach, users can intuitively recognize their privacy status on OSNs. Experiments using real data show that our method can effectively and accurately help users improve their privacy disclosures.

Encapsulation of 2,4-Dihydroxybenzophenone into Dodecylbenzenesulfonate Modified Layered Double Hydroxide for UV Absorption Properties

Li, Shifeng,Shen, Yanming,Liu, Dongbin,Fan, Lihui,Wu, Keke Korean Chemical Society 2014 Bulletin of the Korean Chemical Society Vol.35 No.2

New organic-inorganic composite of 2,4-dihydroxybenzophenone (BP-1) encapsulation into dodecylbenzenesulfonate (DBS) modified layered double hydroxide (LDH) was successfully prepared. The surface, structural, thermal and absorption properties of the BP-1/DBS-LDH nanohybrid was characterized by BET analysis, scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TG) and diffuse reflectance UV-Vis absorbance spectra (DRUV-vis). The interlayer configuration of composite and the adsorption mechanism of BP-1 on MgAl-DBS-LDH were discussed. It was suspected that DBS anions located in the form of monolayer arrangement with a $75^{\circ}$ anti parallel angle between dodecylbenzenesulfonate chain axis. The diffuse reflectance UV-Vis absorbance results revealed that the UV absorbing wavelength of BP-1/DBS-LDH evidently extends to about 400 nm, which shows that the BP-1/DBS-LDH has the potential application as a UV absorber.

Encapsulation of 2,4-Dihydroxybenzophenone into Dodecylbenzenesulfonate Modified Layered Double Hydroxide for UV Absorption Properties

Shifeng Li,Yanming Shen,Dongbin Liu,Lihui Fan,Keke Wu 대한화학회 2014 Bulletin of the Korean Chemical Society Vol.35 No.2

New organic-inorganic composite of 2,4-dihydroxybenzophenone (BP-1) encapsulation into dodecylbenzenesulfonate (DBS) modified layered double hydroxide (LDH) was successfully prepared. The surface, structural, thermal and absorption properties of the BP-1/DBS-LDH nanohybrid was characterized by BET analysis, scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TG) and diffuse reflectance UV-Vis absorbance spectra (DRUV-vis). The interlayer configuration of composite and the adsorption mechanism of BP-1 on MgAl-DBS-LDH were discussed. It was suspected that DBS anions located in the form of monolayer arrangement with a 75° anti parallel angle between dodecylbenzenesulfonate chain axis. The diffuse reflectance UV-Vis absorbance results revealed that the UV absorbing wavelength of BP-1/DBS-LDH evidently extends to about 400 nm, which shows that the BP-1/DBS-LDH has the potential application as a UV absorber.

Intercalation of 2,4-dihydroxybenzophenone-5-sulfonate anion into Zn/Al layered double hydroxides for UV absorption properties

Shifeng Li,Yanming Shen,Min Xiao,Dongbin Liu,Lihui Fan,Keke Wu 한국공업화학회 2014 Journal of Industrial and Engineering Chemistry Vol.20 No.4

Zn/Al-layered double hydroxides (LDHs) containing the organic anion of 2,4-dihydroxybenzophenone-5-sulfonate (DHBS) have been synthesized by co-precipitation method. Surface, structural, thermal and absorption properties of the ZnAl-DHBS-LDHs nanohybrids were characterized by BET analysis, scanning electron microscope, X-ray diffraction, Fourier transform infrared spectroscopy, thermogravimetry and differential thermal analysis and UV–visible spectroscopy. The results revealed that organic UV absorbent-DHBS has been intercalated into the interlayer spaces of ZnAl-LDHs and the intercalation of DHBS in LDHs interlayer galleries resulted to higher thermal stability and better UV absorption ability; these show that the hybrid ZnAl-DHBS-LDHs phase has potential applications as a UV absorber.

Microstructures and Mechanical Properties of Thick Ti–6Al–3Nb–2Zr–1Mo Joint by Magnetron-Controlled Narrow Gap TIG Welding

Laifa Ding,Binhao Qin,Keke Ge,Zhibin Zeng,Khaskin Vladyslav,Feng Li,Yupeng Zhang,Haiyan Wang 대한금속·재료학회 2023 METALS AND MATERIALS International Vol.29 No.8

The butt joint of 30 mm-thick Ti–6Al–3Nb–2Zr–1Mo titanium alloys were achieved by the magnetron-controlled narrow gapTIG welding. Microstructure and mechanical properties of joint were comprehensively explored. Ti6321 base metal (BM)was composed of primary α (accounting for 55%) and structure of β transformation (secondary α + β phase). Fine grainedheat affected zone was composed of primary α, acicular α and β phase. Coarse grained heat affected zone was composed ofacicular α and clusters of α phase with different orientations. The fusion zone (FZ) was composed of acicular α phase, lathα phase and a few β phase. The ratio of high-angle grain boundaries in the HAZ reached the maximum of 94.5% while thoseof the FZ and BM were 78.1% and 59.4%, respectively. Due to the differences in microstructures and grain orientation, thehardness of FZ (286 HV) was lower than those of BM (304 HV) and HAZ (306 HV). The tensile strength of the weldingjoint (838 MPa) reached 95% of the BM (883 MPa), and the joint showed excellent impact performance with great impactenergies of FZ (72 J) and HAZ (75 J), higher than that of BM (51 J). It was owing to the greater ratio of high-angle grainboundaries in FZ and HAZ that could store more grain boundary energies. Thicker phases hinder the growth of cracks, and,therefore, improve the impact performance of the joint.

Research on facility layout optimization algorithm of deep-water semi-submersible drilling platform

Hongyan Wang,Wensheng Xiao,Lei Wu,Keke Wei,Congcong Xu,Chao Hou,Junguo Cui,Jie Li 대한기계학회 2019 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.33 No.2

We aimed to create a facility layout design of semi-submersible drilling platform (DSDP) with performance constraints. The Boltzmann survival mechanism of simulated annealing algorithm was introduced into the replacement strategy of genetic algorithm to form an improved genetic algorithm called genetic and simulated annealing algorithm (GASA). The new algorithm alleviates the “combination explosion” and premature convergence of the traditional genetic algorithm. The layout problem of DSDP is efficiently solved by using this new algorithm. When the number of layout objects increases, GASA’s performance is better than that of the genetic algorithm.