726
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Huang P, Yuan L, Zhang K, Chen Q, Zhou Y, Song B, Li Y. Room-Temperature and Aqueous Solution-Processed Two-Dimensional TiS 2 as an Electron Transport Layer for Highly Efficient and Stable Planar n-i-p Perovskite Solar Cells. ACS APPLIED MATERIALS & INTERFACES 2018; 10:14796-14802. [PMID: 29633824 DOI: 10.1021/acsami.8b03225] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
In this study, a room-temperature and aqueous solution-processed two-dimensional (2D) transition-metal dichalcogenide TiS2 was applied as an electron transport layer (ETL) in planar n-i-p perovskite solar cells (Pero-SCs). Upon insertion of the 2D TiS2 ETL with UV-ozone (UVO) treatment, the power conversion efficiency (PCE) of the planar Pero-SCs was optimized to 18.79%. To the best of our knowledge, this value should be the highest efficiency to date among those PCEs of the n-i-p Pero-SCs with room-temperature-processed metal compound ETLs. More importantly, the n-i-p Pero-SCs with the UVO-treated 2D TiS2 as an ETL also show extremely high stability, where the average PCE remained over 95% of its initial value after 816 h storage without encapsulation.
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727
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Zhu G, Xiao H, Guo Q, Song B, Zheng G, Zhang Z, Zhao J, Okoli CP. Heavy metal contents and enrichment characteristics of dominant plants in wasteland of the downstream of a lead-zinc mining area in Guangxi, Southwest China. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2018; 151:266-271. [PMID: 29407559 DOI: 10.1016/j.ecoenv.2018.01.011] [Citation(s) in RCA: 58] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2017] [Revised: 01/04/2018] [Accepted: 01/07/2018] [Indexed: 05/22/2023]
Abstract
A field investigation on the content of heavy metals in soils and 17 kinds of dominant plants from wasteland of the downstream of a Pb-Zn mine in Northwest Guangxi Zhuang Autonomous Region was carried out. The absorption and accumulation characteristics of heavy metals between plants and soil were compared, and the candidate species for ecosystem restoration of the area were selected. The results indicated that the soils had been subjected to pollution of heavy metals in varying degrees. The concentrations of Cd, Pb, Zn were 46.5, 57.3 and 23.7 times higher than their corresponding background values, respectively. The contents of Cd, Pb and Zn in the most analyzed plants exceed the normal ranges and the phytotoxic level. C. crepidioides, S. nigrum, B. pilosa, C. Canadensis, A. conyzoides, I. denticulata and E. crusgali showed strong capability in accumulation and transport of Cd, and they could be used as good candidates for Cd- phytoextraction. Among which, Cd concentration in the aerial part of C. crepidioides exceeded the threshold of Cd-hyperaccumulator. Thus, C. crepidioides demonstrated the basic characteristics of a Cd-hyperaccumulator. The lower translocation ratios for Cd, Cu, Zn and Pb in P. vittata and C. chinensis make them suitable for phytostabilization in the study area.
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Niu PP, Song B, Xu YM. Letter by Niu et al Regarding Article, "Outcome After Reperfusion Therapies in Patients With Large Baseline Diffusion-Weighted Imaging Stroke Lesions: A THRACE Trial (Mechanical Thrombectomy After Intravenous Alteplase Versus Alteplase Alone After Stroke) Subgroup Analysis". Stroke 2018; 49:e228. [PMID: 29686023 DOI: 10.1161/strokeaha.118.021069] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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729
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Li Y, Niu S, Rakov D, Wang Y, Cabán-Acevedo M, Zheng S, Song B, Xu P. Metal organic framework-derived CoPS/N-doped carbon for efficient electrocatalytic hydrogen evolution. NANOSCALE 2018; 10:7291-7297. [PMID: 29632920 DOI: 10.1039/c8nr01811a] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Electrocatalytic hydrogen evolution has attracted a great deal of attention due to the urgent need for clean energy. Herein, we demonstrate the synthesis of ternary pyrite-type cobalt phosphosulphide (CoPS) nanoparticles supported on a nitrogen-doped carbon matrix, CoPS/N-C, through carbonization and subsequent phosphosulfurization of Co-based zeolitic imidazolate frameworks (ZIF-67), as promising hydrogen evolution reaction (HER) electrocatalysts in both acidic and alkaline solutions. The polyhedral structure of ZIF-67 can be well maintained in the as-prepared CoPS/N-C nanocomposites. In particular, CoPS/N-C provides a geometric catalytic current density of -10 mA cm-2 at overpotentials of -80 and -148 mV vs. a reversible hydrogen electrode (RHE) and a Tafel slope of 68 and 78 mV dec-1 in 0.5 M H2SO4 and 1 M KOH, respectively, which is superior to most of the transition metal phosphosulfide materials. This MOF-derived synthesis of a transition metal phosphosulfide supported heteroatom-doped carbon matrix provides a promising opportunity for the development of highly efficient electrocatalysts for renewable energy devices.
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730
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Niu HX, Wang RH, Xu HL, Song B, Yang J, Shi CH, Li YS, Zhang BQ, Wang SP, Yong Q, Wang YY, Xu YM. Nine-hole Peg Test and Ten-meter Walk Test for Evaluating Functional Loss in Chinese Charcot-Marie-Tooth Disease. Chin Med J (Engl) 2018; 130:1773-1778. [PMID: 28748848 PMCID: PMC5547827 DOI: 10.4103/0366-6999.211550] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Background: The 9-hole peg test (9-HPT) and 10-meter walk test (10-MWT) are commonly used to test finger motor function and walking ability. The aim of this present study was to investigate the efficacy of these tests for evaluating functional loss in Chinese Charcot-Marie-Tooth (CMT) disease. Methods: Thirty-four Chinese CMT patients (CMT group) from August 2015 to December 2016 were evaluated with 9-HPT, 10-MWT, CMT disease examination score, overall neuropathy limitation scale (ONLS), functional disability score, and Berg Balance Scale (BBS). Thirty-five age- and gender-matched healthy controls (control group) were also included in the study. Student's nonpaired or paired t-test were performed to compare data between two independent or related groups, respectively. The Pearson test was used to examine the correlations between recorded parameters. Results: The mean 9-HPT completion time in the dominant hand of CMT patients was significantly slower than that in the healthy controls (29.60 ± 11.89 s vs. 19.58 ± 3.45 s; t = −4.728, P < 0.001). Women with CMT completed the 9-HPT significantly faster than men with CMT (dominant hand: 24.74 ± 7.93 s vs. 33.01 ± 13.14 s, t = 2.097, P = 0.044). The gait speed of the average self-selected velocity and the average fast-velocity assessed using 10-MWT for CMT patients were significantly slower than those in the control group (1.03 ± 0.18 m/s vs. 1.44 ± 0.17 m/s, t = 9.333, P < 0.001; 1.31 ± 0.30 m/s vs. 1.91 ± 0.25 m/s, t = 8.853, P < 0.001, respectively). There was no difference in gait speed between men and women. Both 9-HPT and 10-MWT were significantly correlated with the ONLS, functional disability score, and BBS (P < 0.05 for all). Conclusion: The 9-HPT and 10-MWT might be useful for functional assessment in Chinese patients with CMT.
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731
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Song B, Yang ZJ, Zhang YX, Wang FP, Zhou L, Li L, Zhong XM. [Accumulation of Cd and Its Risks in the Soils of the Xijiang River Drainage Basin in Guangxi]. HUAN JING KE XUE= HUANJING KEXUE 2018; 39:1888-1900. [PMID: 29965016 DOI: 10.13227/j.hjkx.201707238] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
To understand the distribution and risk of soil cadmium (Cd) in the Xijiang River drainage basin in Guangxi, a total of 2512 soil samples were collected nonferrous metal mining area, farmland (paddy soils and dryland soils) and the background soils, in the Xijiang River drainage basin in Guangxi.The results showed that Cd concentration was 0.514 mg·kg-1 in background soils significantly higher than previously resulted(0.148 mg·kg-1)and that in Guangxi background soil(0.267 mg·kg-1). The geometric average concentration of Cd in dryland soils, paddysoils and mining soils was 0.559, 0.787, 5.71 mg·kg-1, respectively, which were significantly higher than background soils. The Cd concentration exceeded the background soils and baseline by 51.2% and 35.2% in dryland soil, 66.7% and 39.6% in paddy soil, 77.8% and 71.4% in mining soil, high Cd concentration occurred in the Nandan County, Dahua County, Duan County, Huanjiang County and Yizhou City, as well as Liujiang County, These regions have developed severe and even extremely serious pollution, medium-high pollution accumulation and higher-extremely high potential ecological risks. The Cd-pollution in soils in agricultural and mining soils in upstream of Xijiang River in Guangxi is serious, due to mining activities and high Cd geological background. People in the mining area and surrounding areas who live on local crops, vegetables, may expose to the Cd-pollution. It is recommended to further develop a Cd risk assessment through a soil-plant-human system, taking appropriate measures to control risk.
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732
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Miao P, Qin JK, Shen Y, Su H, Dai J, Song B, Du Y, Sun M, Zhang W, Wang HL, Xu CY, Xu P. Unraveling the Raman Enhancement Mechanism on 1T'-Phase ReS 2 Nanosheets. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2018; 14:e1704079. [PMID: 29411513 DOI: 10.1002/smll.201704079] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2017] [Revised: 12/19/2017] [Indexed: 06/08/2023]
Abstract
2D transition metal dichalcogenides materials are explored as potential surface-enhanced Raman spectroscopy substrates. Herein, a systematic study of the Raman enhancement mechanism on distorted 1T (1T') rhenium disulfide (ReS2 ) nanosheets is demonstrated. Combined Raman and photoluminescence studies with the introduction of an Al2 O3 dielectric layer unambiguously reveal that Raman enhancement on ReS2 materials is from a charge transfer process rather than from an energy transfer process, and Raman enhancement is inversely proportional while the photoluminescence quenching effect is proportional to the layer number (thickness) of ReS2 nanosheets. On monolayer ReS2 film, a strong resonance-enhanced Raman scattering effect dependent on the laser excitation energy is detected, and a detection limit as low as 10-9 m can be reached from the studied dye molecules such as rhodamine 6G and methylene blue. Such a high enhancement factor achieved through enhanced charge interaction between target molecule and substrate suggests that with careful consideration of the layer-number-dependent feature and excitation-energy-related resonance effect, ReS2 is a promising Raman enhancement platform for sensing applications.
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733
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Ren M, Song B, Zhuang T, Yang S. Optical partial discharge diagnostic in SF 6 gas insulated system via multi-spectral detection. ISA TRANSACTIONS 2018; 75:247-257. [PMID: 29475605 DOI: 10.1016/j.isatra.2018.02.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/08/2017] [Revised: 01/06/2018] [Accepted: 02/07/2018] [Indexed: 06/08/2023]
Abstract
Light emitted from partial discharges (PDs) in SF6 gas is investigated in the view point of insulation status diagnostics. Light intensity and integral spectrum of PD are proved to have significant correlations with PD activities and the involved dielectric interfaces. Based on synchronous light pulse detections in ultraviolet (UV), visible (VIS) and near-infrared (NIR) regions, the multispectral stochastic PD diagnosis is realized with more information beyond the conventional PD detections. The optical PD detection is also compared with ultra-high frequency (UHF) PD detection and acoustic emission (AE) PD detection in term of linearity, sensitivity and statistical property. Beyond that, a clustering analysis is performed on the multispectral photon counts of different conditions by quantifying them in a ternary diagram where some distinguishable regions emerge for PD recognition.
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734
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Liu Y, Chen Y, Li S, Shu C, Fang Y, Song B. Improved Charge Transfer in a Mn 2O 3@Co 1.2Ni 1.8O 4 Hybrid for Highly Stable Alkaline Direct Methanol Fuel Cells with Good Methanol Tolerance. ACS APPLIED MATERIALS & INTERFACES 2018; 10:9485-9494. [PMID: 29494130 DOI: 10.1021/acsami.8b00613] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
A three-dimensional Mn2O3@Co1.2Ni1.8O4 hybrid was synthesized via facile two-step processes and employed as a cathode catalyst in direct methanol fuel cells (DMFCs) for the first time. Because of the unique architecture with ultrathin and porous nanosheets of the Co1.2Ni1.8O4 shell, this composite exhibits better electrochemical performance than the pristine Mn2O3. Remarkably, it shows excellent methanol tolerance, even in a high concentration solution. The DMFC was assembled with Mn2O3@Co1.2Ni1.8O4, polymer fiber membranes, and PtRu/C as the cathode, membrane, and anode, respectively. The power densities of 57.5 and 70.5 mW cm-2 were recorded at 18 and 28 °C, respectively, especially the former is the best result reported in the literature at such a low temperature. The stability of the Mn2O3@Co1.2Ni1.8O4 catalyzed cathode was evaluated, and the results show that this compound possesses excellent stability in a high methanol concentration. The improved electrochemical activity could be attributed to the narrow band gap of the hybrid, which accelerates the electrons jumping from the valence band to the conduction band. Therefore, MnIII could be oxidized into MnIV more easily, simultaneously providing an electron to the absorbed oxygen.
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735
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Zhu W, Wang Y, Yan F, Song R, Li Z, Li Y, Song B. Physical and chemical properties, percutaneous absorption-promoting effects of exopolysaccharide produced by Bacillus atrophaeus WYZ strain. Carbohydr Polym 2018; 192:52-60. [PMID: 29691034 DOI: 10.1016/j.carbpol.2018.03.063] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2017] [Revised: 03/01/2018] [Accepted: 03/18/2018] [Indexed: 11/28/2022]
Abstract
A high yield of exopolysaccharides bacteria isolated from mangrove system was identified as Bacillus atrophaeus by 16S rDNA and named as WYZ strain. An exopolysaccharide (BPS) was obtained from this strain after purification with a yield of about 0.58 g/L. Then some physical and chemical properties of BPS, such as weight average molecular weight (Mw), monosaccharide composition, intrinsic viscosity and water retention capacity were studied. The microstructure (SEM) showed that BPS was porous wound three-dimensional spider web structure. Using BPS as transdermal absorption enhancer, and lidocaine as a test drug, in vitro and local anesthesia in live animals experiments were conducted to explore that the BPS promote lidocaine transdermal absorption and mechanism. In conclusion, the BPS had good water retention capacity and transdermal absorption promoting effect, all of these indicated that BPS has great potential in the field of biomaterials.
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736
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Song B, Stöcklin J, Armbruster WS, Gao Y, Peng D, Sun H. Reversible colour change in leaves enhances pollinator attraction and reproductive success in Saururus chinensis (Saururaceae). ANNALS OF BOTANY 2018; 121:641-650. [PMID: 29325003 PMCID: PMC5853024 DOI: 10.1093/aob/mcx195] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2017] [Accepted: 11/27/2017] [Indexed: 05/10/2023]
Abstract
Background and Aims Although there has been much experimental work on leaf colour change associated with selection generated by abiotic environmental factors and antagonists, the role of leaf colour change in pollinator attraction has been largely ignored. We tested whether whitening of the apical leaves subtending the inflorescences of Saururus chinensis during flowering enhances pollinator attraction, and whether re-greening of the white leaves after flowering increases carbon assimilation and promotes seed development. Methods White leaves were removed or covered, and the effects of these manipulations on pollinator visitation and subsequent reproductive success were assessed. The net photosynthetic rates of leaves of different colour were measured and their photosynthetic contributions to seed development were evaluated. Key Results Saururus chinensis is able to self-pollinate autonomously, but depends largely on flies for pollination. White leaves had different reflectance spectra from green leaves, and white leaves attracted significantly more pollinators and led to significantly higher fruit and seed set. Although leaf whitening resulted in a reduction in photosynthetic capacity, it translated into only a small decrease in seed mass. When leaves had turned back from white to green after flowering their photosynthetic capacity was similar to that of 'normal' green leaves and promoted seed development. Conclusions The reversible leaf colour change in S. chinensis appears to be adaptive because it enhances pollination success during flowering, with a small photosynthetic cost, while re-greening of these leaves after flowering helps to meet the carbon requirements for seed development.
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737
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Jiang X, Gao Y, Lal R, Hu J, Song B. Asymmetry induces Q-band split in the electronic excitations of magnesium porphyrin. Mol Phys 2018. [DOI: 10.1080/00268976.2018.1444207] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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738
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Du Z, Song B, Zhang W, Duan C, Wang YL, Liu C, Zhang R, Yuan J. Quantitative Monitoring and Visualization of Hydrogen Sulfide In Vivo Using a Luminescent Probe Based on a Ruthenium(II) Complex. Angew Chem Int Ed Engl 2018. [DOI: 10.1002/ange.201800540] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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739
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Du Z, Song B, Zhang W, Duan C, Wang YL, Liu C, Zhang R, Yuan J. Quantitative Monitoring and Visualization of Hydrogen Sulfide In Vivo Using a Luminescent Probe Based on a Ruthenium(II) Complex. Angew Chem Int Ed Engl 2018; 57:3999-4004. [DOI: 10.1002/anie.201800540] [Citation(s) in RCA: 85] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2018] [Revised: 01/30/2018] [Indexed: 11/10/2022]
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740
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Lou DM, Geng XY, Song B, Tan PQ, Hu ZY, Liu JY. [Particulate Component Emission Characteristic from a Diesel Bus with DOC and CDPF]. HUAN JING KE XUE= HUANJING KEXUE 2018; 39:1040-1045. [PMID: 29965447 DOI: 10.13227/j.hjkx.201705049] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A diesel bus was tested with a China City Bus Cycle (CCBC) on a heavy chassis dynamometer, and the components of the particulate emissions with different after-treatment equipment were investigated. Results showed that OC was less than EC in the particulates of the bus emissions without the use of after-treatment equipment. The organic components were mainly fatty acids (60.9%) and n-alkanes (32.4%), with a few hopanes and PAHs. Fatty acid components were mainly C16:0, C18, C14, and C18:1. The n-alkanes were mainly C18-C24, with C21H44 and C22H46 accounting for the greatest portion. PAH mass was concentrated in medium and small molecular weight components, such as Pyr, FL, and PA. While PAH toxicity was dominated by medium and high molecular weight components, BaP was the most toxic, followed by B(b+k)F, BaA, and IcdP. The total toxicity of the PAHs decreased by 2.7% after DOC treatment and continued to decrease by 89.6%-93.8% after CDPF treatment. After-treatment equipment significantly reduced the OC+EC emissions by 18.9% (DOC) and 70.5%-72.5% (CDPF), but the reduction rate varied from one component to another. The different precious metal loadings of the CDPF did not obviously affect the reduction rate.
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Shang D, Song B, Liu Y. Epirubicin suppresses proliferative and metastatic potential by downregulating transforming growth factor-β-induced expression in urothelial carcinoma. Cancer Sci 2018; 109:980-987. [PMID: 28940965 PMCID: PMC5891197 DOI: 10.1111/cas.13403] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2017] [Revised: 09/13/2017] [Accepted: 09/18/2017] [Indexed: 12/29/2022] Open
Abstract
Transforming growth factor‐β‐induced (TGFΒI) is considered to be a vital gene in several carcinomas. In this study we determined the effect of TGFBI on the proliferative and metastatic potential of human urothelial carcinoma (UC) cells as well as its mRNA and protein expression, which were detected by RT‐PCR and western blot, respectively. UC cell proliferation was analyzed by WST‐1 assay and Hoechst 33258 staining. The effect of TGFBI on UC cell metastasis was analyzed using adhesion, migration and invasion assays. We found that TGFBI increased the proliferation of UC cells. Moreover, TGFBI enhanced the adhesion, migration and invasion of UC cells by upregulating MMP‐2, MMP‐9 and calpain‐2 expression. We evaluated the effect of Epirubicin (EPI) on the regulation of TGFBI expression and found that TGFBI acts as a downstream target of EPI and is suppressed by EPI in UC cells. EPI is more effective in inhibiting the proliferation and metastasis of UC cells with high TGFBI expression. This study demonstrates that TGFBI might lead to tumorigenesis and progression of UC and those cells with high TGFBI expression may be vulnerable to relapse. EPI could prove to be a therapeutic option in patients with high TGFBI expressing UC cells.
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Song B, Hamdan SM, Hingorani MM. Positioning the 5'-flap junction in the active site controls the rate of flap endonuclease-1-catalyzed DNA cleavage. J Biol Chem 2018; 293:4792-4804. [PMID: 29462789 DOI: 10.1074/jbc.ra117.001137] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2017] [Revised: 02/08/2018] [Indexed: 12/14/2022] Open
Abstract
Flap endonucleases catalyze cleavage of single-stranded DNA flaps formed during replication, repair, and recombination and are therefore essential for genome processing and stability. Recent crystal structures of DNA-bound human flap endonuclease (hFEN1) offer new insights into how conformational changes in the DNA and hFEN1 may facilitate the reaction mechanism. For example, previous biochemical studies of DNA conformation performed under non-catalytic conditions with Ca2+ have suggested that base unpairing at the 5'-flap:template junction is an important step in the reaction, but the new structural data suggest otherwise. To clarify the role of DNA changes in the kinetic mechanism, we measured a series of transient steps, from substrate binding to product release, during the hFEN1-catalyzed reaction in the presence of Mg2+ We found that whereas hFEN1 binds and bends DNA at a fast, diffusion-limited rate, much slower Mg2+-dependent conformational changes in DNA around the active site are subsequently necessary and rate-limiting for 5'-flap cleavage. These changes are reported overall by fluorescence of 2-aminopurine at the 5'-flap:template junction, indicating that local DNA distortion (e.g. disruption of base stacking observed in structures), associated with positioning the 5'-flap scissile phosphodiester bond in the hFEN1 active site, controls catalysis. hFEN1 residues with distinct roles in the catalytic mechanism, including those binding metal ions (Asp-34 and Asp-181), steering the 5'-flap through the active site and binding the scissile phosphate (Lys-93 and Arg-100), and stacking against the base 5' to the scissile phosphate (Tyr-40), all contribute to these rate-limiting conformational changes, ensuring efficient and specific cleavage of 5'-flaps.
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Liu C, Song B, Zhang YX, Lei M, Tian ML, Yu YY, Pang R. [Spatial Variability and Contamination of Arsenic in Soils of Xijiang River Basin]. HUAN JING KE XUE= HUANJING KEXUE 2018; 39:899-908. [PMID: 29964856 DOI: 10.13227/j.hjkx.201708244] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
In this study, 2585 soil samples were collected in the Xijiang River Basin in Guangxi Zhuang Autonomous Region and the spatial variability and contamination of Arsenic in soils were evaluated using geostatistical and GIS tools. The results showed that the concentrations of As in surface soils (23.82 mg·kg-1) were higher than the background values of the Guangxi and Xijiang Rivers in natural soils; the upstream values (Diaojiang River and Huanjiang River) (30.22 mg·kg-1) were significantly higher than those in other regions. Concentrations of As in soil samples were in the order of soil in mining areas > soil in dryland > natural soil > paddy soil. As in mining areas were significantly higher than in other areas; high As concentrations were measured in the upstream of the Diaojiang River basin and the downstream of the Huanjiang River Basin. Low concentration clusters were in the six villages of Nandan, which are far from the mine, and in the upper reaches of the Dahuanjiang River and Xiaohuanjiang River Basin. Spatial autocorrelations of arsenic in the watershed soil were evident and the structural variability was dominant. The concentration of As in the upper reaches decreased from the northwest to the southeast. High As concentrations were distributed naturally along the river basin; concentrations in the middle and lower reaches of the basin were between 0.44 mg·kg-1 and 40 mg·kg-1. The concentration levels of As in total soil samples ranged from no-pollution to slight pollution, and the pollution was mainly distributed in the administrative areas of the city and the intensive areas of mining activities, among which the soil pollution in Jinchengjiang River and Nandan counties was more prominent. Effective measures should be taken to strengthen the safety level of tailings reservoirs during the rainy season, so as to maintain the production levels while protecting living standards of local residents.
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744
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Yin GQ, Wang H, Wang XQ, Song B, Chen LJ, Wang L, Hao XQ, Yang HB, Li X. Self-assembly of emissive supramolecular rosettes with increasing complexity using multitopic terpyridine ligands. Nat Commun 2018; 9:567. [PMID: 29422628 PMCID: PMC5805703 DOI: 10.1038/s41467-018-02959-w] [Citation(s) in RCA: 106] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2017] [Accepted: 01/10/2018] [Indexed: 01/16/2023] Open
Abstract
Coordination-driven self-assembly has emerged as a powerful bottom-up approach to construct various supramolecular architectures with increasing complexity and functionality. Tetraphenylethylene (TPE) has been incorporated into metallo-supramolecules to build luminescent materials based on aggregation-induced emission. We herein report three generations of ligands with full conjugation of TPE with 2,2':6',2″-terpyridine (TPY) to construct emissive materials. Due to the bulky size of TPY substituents, the intramolecular rotations of ligands are partially restricted even in dilute solution, thus leading to emission in both solution and aggregation states. Furthermore, TPE-TPY ligands are assembled with Cd(II) to introduce additional restriction of intramolecular rotation and immobilize fluorophores into rosette-like metallo-supramolecules ranging from generation 1-3 (G1-G3). More importantly, the fluorescent behavior of TPE-TPY ligands is preserved in these rosettes, which display tunable emissive properties with respect to different generations, particularly, pure white-light emission for G2.
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745
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Cao S, Jiao Y, Han W, Ge C, Song B, Wang J, Zhang X. Hydrothermal synthesis of 4ZnO·B 2O 3·H 2O:Ln 3+ (Ln=Eu, Tb) phosphors: Morphology-tunable and luminescence properties. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2018; 190:231-238. [PMID: 28934701 DOI: 10.1016/j.saa.2017.09.040] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2017] [Revised: 09/11/2017] [Accepted: 09/15/2017] [Indexed: 06/07/2023]
Abstract
4ZnO·B2O3·H2O:Ln3+ (Ln=Eu, Tb) phosphors with different morphologies have been successfully synthesized via one-step hydrothermal method through regulating the molar amount of Eu3+ and Tb3+. Comprehensive scanning electron microscopy (SEM), X-ray diffraction (XRD) Fourier transform infrared spectrum (FT-IR) and inductively coupled plasma atomic emission spectrometer (ICP-AES) characterizations all confirm that obtained products are 4ZnO·B2O3·H2O:Ln3+ (Ln=Eu, Tb). The experimental results displayed that the morphology and photoluminescence of compounds is regularly changed with increased the molar amount of rare earth ions. For the Eu3+-doped, Tb3+-doped and Eu3+/Tb3+ co-doped 4ZnO·B2O3·H2O phosphors of morphologies, the rod-like structures gradually changed to flower-like structures, fine wire-like structure and hybrid structure, respectively. To their photoluminescence, the Eu3+ shows a red emission (615nm); the Tb3+ shows a green emission (545nm); for the Eu3+/Tb3+ co-doped 4ZnO·B2O3·H2O phosphors, a combination of blue (5d-4f of Eu2+), green (5D4-7F5 of Tb3+) and red (5D0-7F2 of Eu3+) emissions emerges to achieve white emission. In addition, the energy transfer among Eu3+, Eu2+ and Tb3+ ions was also discussed.
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746
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Krishnan HB, Song B, Oehrle NW, Cameron JC, Jez JM. Impact of overexpression of cytosolic isoform of O-acetylserine sulfhydrylase on soybean nodulation and nodule metabolome. Sci Rep 2018; 8:2367. [PMID: 29402985 PMCID: PMC5799319 DOI: 10.1038/s41598-018-20919-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2017] [Accepted: 01/25/2018] [Indexed: 01/05/2023] Open
Abstract
Nitrogen-fixing nodules, which are also major sites of sulfur assimilation, contribute significantly to the sulfur needs of whole soybean plants. Nodules are the predominant sites for cysteine accumulation and the activity of O-acetylserine(thiol)lyase (OASS) is central to the sulfur assimilation process in plants. Here, we examined the impact of overexpressing OASS on soybean nodulation and nodule metabolome. Overexpression of OASS did not affect the nodule number, but negatively impacted plant growth. HPLC measurement of antioxidant metabolites demonstrated that levels of cysteine, glutathione, and homoglutathione nearly doubled in OASS overexpressing nodules when compared to control nodules. Metabolite profiling by LC-MS and GC-MS demonstrated that several metabolites related to serine, aspartate, glutamate, and branched-chain amino acid pathways were significantly elevated in OASS overexpressing nodules. Striking differences were also observed in the flavonoid levels between the OASS overexpressing and control soybean nodules. Our results suggest that OASS overexpressing plants compensate for the increase in carbon requirement for sulfur assimilation by reducing the biosynthesis of some amino acids, and by replenishing the TCA cycle through fatty acid hydrolysis. These data may indicate that in OASS overexpressing soybean nodules there is a moderate decease in the supply of energy metabolites to the nodule, which is then compensated by the degradation of cellular components to meet the needs of the nodule energy metabolism.
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747
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Anaissie J, Haney N, Song B, Brabadi Z, Chen T, Swan K, Reddy A, DeLay K, Alzweri L, Kadowitz P, Hellstrom W, Izadpanah R. 164 The Effects of Multiple Adipose-Derived Stem Cell Intracorporeal Injections on Erectile Dysfunction in a Rat Model of Cavernosal Nerve Injury. J Sex Med 2018. [DOI: 10.1016/j.jsxm.2017.11.123] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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748
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Song B, Zhang L, He C, Poon TFJ, Hajiyev E, Zhang S, Liu XJ, Jo GB. Observation of symmetry-protected topological band with ultracold fermions. SCIENCE ADVANCES 2018; 4:eaao4748. [PMID: 29492457 PMCID: PMC5825217 DOI: 10.1126/sciadv.aao4748] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2017] [Accepted: 01/23/2018] [Indexed: 05/22/2023]
Abstract
Symmetry plays a fundamental role in understanding complex quantum matter, particularly in classifying topological quantum phases, which have attracted great interests in the recent decade. An outstanding example is the time-reversal invariant topological insulator, a symmetry-protected topological (SPT) phase in the symplectic class of the Altland-Zirnbauer classification. We report the observation for ultracold atoms of a noninteracting SPT band in a one-dimensional optical lattice and study quench dynamics between topologically distinct regimes. The observed SPT band can be protected by a magnetic group and a nonlocal chiral symmetry, with the band topology being measured via Bloch states at symmetric momenta. The topology also resides in far-from-equilibrium spin dynamics, which are predicted and observed in experiment to exhibit qualitatively distinct behaviors in quenching to trivial and nontrivial regimes, revealing two fundamental types of spin-relaxation dynamics related to bulk topology. This work opens the way to expanding the scope of SPT physics with ultracold atoms and studying nonequilibrium quantum dynamics in these exotic systems.
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749
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Zhang R, Song B, Yuan J. Bioanalytical methods for hypochlorous acid detection: Recent advances and challenges. Trends Analyt Chem 2018. [DOI: 10.1016/j.trac.2017.11.015] [Citation(s) in RCA: 132] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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750
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Miao P, Huang W, Gao M, Chu J, Song B, Xu P. Photothermally Enhanced Plasmon-Driven Catalysis on Fe5
C2
@Au Core-Shell Nanostructures. ChemCatChem 2018. [DOI: 10.1002/cctc.201701901] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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