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heavy ion

Lan Ling, Xiao-Yue Huang, Meirong Li, Wei-Xian Zhang
Nanoscale zero-valent iron (nZVI) posseses unique functionalities for metal-metalloid removal and sequestration. So far, direct evidence on the heavy metal-iron reactions in the solid phase is still limited due to low concentration of heavy metals and small size of nanoparticles. In this work, angstrom-resolution spectral mappings on the reactions of nZVI with chromate, arsenate, nickel, silver, cesium, and zinc ions are presented. This work was achieved with spherical aberration-corrected scanning transmission electron microscopy integrated with high-sensitivity X-ray energy-dispersive spectroscopy scanning transmission electron microscopy (XEDS-STEM)...
November 17, 2017: Environmental Science & Technology
Ulrich-Axel Bommer
The Translational Controlled Tumour Protein TCTP (gene symbol TPT1, also called P21, P23, Q23, fortilin or histamine-releasing factor, HRF) is a highly conserved protein present in essentially all eukaryotic organisms and involved in many fundamental cell biological and disease processes. It was first discovered about 35 years ago, and it took an extended period of time for its multiple functions to be revealed, and even today we do not yet fully understand all the details. Having witnessed most of this history, in this chapter, I give a brief overview and review the current knowledge on the structure, biological functions, disease involvements and cellular regulation of this protein...
2017: Results and Problems in Cell Differentiation
Florian Lackner, Günter Krois, Wolfgang E Ernst
The electronic excitation spectrum of lithium atoms residing on the surface of helium nanodroplets is presented and analyzed employing a Rydberg-Ritz approach. Utilizing resonant two-photon ionization spectroscopy, two different Rydberg series have been identified: one assigned to the nS(Σ) series and the other with predominantly nP(Π) character. For high Rydberg states, which have been resolved up to n = 13, the surrounding helium effectively screens the valence electron from the Li ion core, as indicated by the apparent red-shift of Li transitions and lowered quantum defects on the droplet with respect to their free atom counterparts...
November 14, 2017: Journal of Chemical Physics
Ashraf M M Essa, Mohamed A Al Abboud, Sayeed I Khatib
Microorganisms can modify the chemical and physical characters of metals leading to an alteration in their speciation, mobility, and toxicity. Aqueous heavy metals solutions (Hg, Cd, Pb, Ag, Cu, and Zn) were treated with the volatile metabolic products (VMPs) of Escherichia coli Z3 for 24 h using aerobic bioreactor. The effect of the metals treated with VMPs in comparison to the untreated metals on the growth of E. coli S1 and Staphylococcus aureus S2 (local isolates) was examined. Moreover, the toxic properties of the treated and untreated metals were monitored using minimum inhibitory concentration assay...
November 15, 2017: Journal of Basic Microbiology
Jeffrey Yim, Hyokeun Cho, Simon W Rabkin
Gene expression and associations were examined in a model of heart failure with preserved ejection fraction (HFpEF), a condition with minimal effective treatment. Genes with at least two studies showing significant changes in Dahl rat with heart failure were examined by meta-analysis. Significantly increased in expression were iNOS, p47phox, ADM, ANP, OPN, ACE, MCP-1, GP91PHOX, ICAM-1, TGF-β1, CTGF, ET-1, p22phox, ETB, BNP, ETA, MMP13, Col1a1, MMP2, TIMP1, Col3a1, Il-1β, β-MHC, ECE1, MMP14, AGT, and MMP9...
November 15, 2017: Clinical and Experimental Hypertension: CHE
Bin Gong, Yaotian Peng, Ziyan Pan, Weiming Chen, Yi Shen, Kaijun Xiao, Ling Zhang
Herein, gram-scale monodisperse sulfonated polystyrene (SPS) nanospheres are synthesized and examined as a sorbent for the removal of heavy metal ions (Pb(2+), Zn(2+) and Cu(2+)). The resulting uniform SPS nanospheres exhibit remarkable adsorption capabilities and kinetics, facile regeneration and outstanding recyclability, affording promising applications in food engineering and water cleanup.
November 15, 2017: Chemical Communications: Chem Comm
Brendan Whelan, Miriam Welgampola, Leigh McGarvie, Kuldeep Makhija, Robin M Turner, Lois Holloway, Ilana Feain, Michael Jackson, Michael Barton, Paul Keall
INTRODUCTION: Patient rotation could greatly simplify radiation therapy delivery, with particularly important ramifications for fixed beam treatment with protons, heavy ions, MRI-Linacs, and low cost Linacs. Patient tolerance is often cited as a barrier to widespread implementation to patient rotation; however, no quantitative data addressing this issue exists. In this study, patient reported experiences of slow, single arc rotation in upright (sitting) and lying orientations are reported...
November 15, 2017: Journal of Medical Imaging and Radiation Oncology
Yingying Liu, Wenhong Fan, Zhizhen Xu, Weihua Peng, Shenglian Luo
Although the risk of graphene materials to aquatic organisms has drawn wide attention, the combined effects of graphene materials with other contaminants such as toxic metals, which may bring about more serious effects than graphene materials alone, have seldom been explored. Herein, the effects of graphene (GN) and graphene oxide (GO, an important oxidized derivative of graphene) on copper (Cu) toxicity to Daphnia magna were systematically investigated. The results indicated that GN remarkably increased the Cu accumulation in D...
November 11, 2017: Environmental Pollution
Shadpour Mallakpour, Amir Abdolmaleki, Farbod Tabesh
This article reports the first incorporation of calcium carbonate nanoparticles (CC NPs) into tragacanth gum (TG) to prepare a new hydrogel nanocomposite (HNC) system using a green, safe, and eco-friendly method, ultrasound irradiation as an efficient biosorbent of heavy metal ions from wastewater. Morphological studies revealed that the surface of obtained HNCs is rough, homogeneous, and porous-like due to the embedding of CC NPs as well as sonication in comparison to the neat TG which has a smooth surface...
March 2018: Ultrasonics Sonochemistry
Yuanyuan Lu, Xinqiang Liang, Christophe Niyungeko, Junjie Zhou, Jianming Xu, Guangming Tian
Currently, environmental pollution by heavy metals is a global problem. Therefore, it is crucial to develop effective detection techniques to determine the levels of heavy metal contamination in various mediums. Voltammetry is a highly sensitive electrochemical method used for the in situ detection of heavy metal ions. This study investigates the current trends related to electrode modification, developments in materials, and optimization of the experimental parameters. We discuss the sensing performance of four kinds of nanomaterials capable of inorganic modification (metal nanoparticles, metal oxides, carbonaceous nanomaterials, and their nanocomposites)...
February 1, 2018: Talanta
Takeshi Takata, Jun'ichi Kotoku, Hideyuki Maejima, Shinobu Kumagai, Norikazu Arai, Takenori Kobayashi, Kenshiro Shiraishi, Masayoshi Yamamoto, Hiroshi Kondo, Shigeru Furui
To minimise the radiation dermatitis related to interventional radiology (IR), rapid and accurate dose estimation has been sought for all procedures. We propose a technique for estimating the patient skin dose rapidly and accurately using Monte Carlo (MC) simulation with a graphical processing unit (GPU, GTX 1080; Nvidia Corp.). The skin dose distribution is simulated based on an individual patient's computed tomography (CT) dataset for fluoroscopic conditions after the CT dataset has been segmented into air, water and bone based on pixel values...
November 10, 2017: Journal of Radiation Research
Erica Ciotta, Stefano Paoloni, Maria Richetta, Paolo Prosposito, Pietro Tagliatesta, Chiara Lorecchio, Iole Venditti, Ilaria Fratoddi, Stefano Casciardi, Roberto Pizzoferrato
A novel type of graphene-like quantum dots, synthesized by oxidation and cage-opening of C60 buckminsterfullerene, has been studied as a fluorescent and absorptive probe for heavy-metal ions. The lattice structure of such unfolded fullerene quantum dots (UFQDs) is distinct from that of graphene since it includes both carbon hexagons and pentagons. The basic optical properties, however, are similar to those of regular graphene oxide quantum dots. On the other hand, UFQDs behave quite differently in the presence of heavy-metal ions, in that multiple sensitivity to Cu(2+), Pb(2+) and As(III) was observed through comparable quenching of the fluorescent emission and different variations of the transmittance spectrum...
November 14, 2017: Sensors
Lijun Zhang, Xinyan Huang, Yuan Cao, Yunhong Xin, Liping Ding
Enormous effort has been put to the detection and recognition of various heavy metal ions due to their involvement in serious environmental pollution and many major diseases. The present work developed a single fluorescent sensor ensemble that can distinguish and identify a variety of heavy metal ions. A pyrene-based fluorophore (PB) containing a metal ion receptor group was specially designed and synthesized. Anionic surfactant SDS assemblies can effectively adjust its fluorescence behavior. The selected binary ensemble based on PB/SDS assemblies can exhibit multiple emission bands and provide wavelength-based cross-reactive responses to a series of metal ions to realize pattern recognition ability...
November 14, 2017: ACS Sensors
J Felix Shin, Hongjun Niu, Jonathan Alaria, John B Claridge, Matthew J Rosseinsky
Highly dense CaMn1-xRexO3 (0 ≤ x ≤ 0.04) samples were prepared by solid-state synthesis. The effect of Re doping was assessed by the characterisation of crystal structure, oxygen content, and electrical and thermal transport properties. The oxidation state of the substituted Re was determined by X-ray absorption near edge spectra to be Re(7+), and led to expansion of the lattice and an increase in electron carrier concentration due to the formation of Mn(3+). The thermal behaviour of the electrical conductivity and the thermopower over a wide temperature range allowed identification of different conduction mechanisms: (1) below 110 K, 3D variable range hopping, (2) between 110 and 650 K, small polaron transport, and (3) above 650 K, activation of carriers over a mobility edge...
November 14, 2017: Physical Chemistry Chemical Physics: PCCP
Rui Xiong, Ho Shin Kim, Shuaidi Zhang, Sunghan Kim, Volodymyr F Korolovych, Ruilong Ma, Yaroslava G Yingling, Canhui Lu, Vladimir V Tsukruk
The construction of multilength scaled hierarchical nanostructures from diverse natural components is critical in the progress toward all-natural nanocomposites with structural robustness and versatile added functionalities. Here, we report a spontaneous formation of peculiar "shish kebab" nanostructures with the periodic arrangement of silk fibroin domains along straight segments of cellulose nanofibers. We suggest that the formation of these shish kebab nanostructures is facilitated by the preferential organization of heterogeneous (β-sheets and amorphous silk) domains along the cellulose nanofiber driven by modulated axial distribution of crystalline planes, hydrogen bonding, and hydrophobic interactions as suggested by all-atom molecular dynamic simulations...
November 17, 2017: ACS Nano
Stanislav D Anastyuk, Natalia M Shevchenko, Kristina V Belokozova, Pavel S Dmitrenok
A procedure for the partial depolymerization of sulfated fucans and selective labeling with (18)O was developed. A tandem electrospray ionization mass spectrometry (ESI MS/MS) was applied for the direct analysis of mixtures of structurally-different oligosaccharides, derived from the fucoidans of known structure. The presence of label allowed unambiguous distinguishing between the fragment ions of (0,2)X0-type at m/z 287 and (2,4)A-type at m/z 285, since (18)O at the reducing end gave +2 mass shifting. Thus, ESI MS/MS was able to detect (1,2)-type of linkage in disaccharides from the fucoidan of brown alga S...
November 4, 2017: Carbohydrate Research
Jiajia Gao, Kun Wang, Yong Wang, Shuhan Liu, Chuanyong Zhu, Jiming Hao, Huanjia Liu, Shenbing Hua, Hezhong Tian
PM2.5 and its major chemical compositions were sampled and analyzed in January, April, July and October of 2014 at Beijing (BJ), Tianjin (TJ), Langfang (LF) and Baoding (BD) in order to probe the temporal and spatial characteristics as well as source apportionment of PM2.5 in the Beijing-Tianjin-Hebei (BTH) region. The results showed that PM2.5 pollution was severe in the BTH region. The average annual concentrations of PM2.5 at four sampling sites were in the range of 126-180 μg/m(3), with more than 95% of sampling days exceeding 35 μg/m(3), the limit ceiling of average annual concentration of PM2...
November 7, 2017: Environmental Pollution
Bing Tan, Huimin Zhao, Yaobin Zhang, Xie Quan, Zehao He, Wenting Zheng, Bingyu Shi
Phytic acid (PA) induced graphene macrostructures were synthesized and investigated for the sorption characteristics and mechanisms of mercury. The as-synthesized graphene foam possessed large specific surface area and amphiphilicity. FTIR and XPS analysis revealed that the as-prepared graphene macrostructure retained oxygen-containing functional groups after hydrothermal reduction and also captured new phosphorus-containing groups because of the introduction of PA. Different experimental parameters, such as pH, PA fractions and contact time were applied to probe into the Hg(II) adsorption performance of as-synthesized macrostructure...
October 26, 2017: Journal of Colloid and Interface Science
Wenchao Yu, Fei Lian, Guannan Cui, Zhongqi Liu
N-doping was successfully employed to improve the adsorption capacity of biochar (BC) for Cu(2+) and Cd(2+) by direct annealing of crop straws in NH3. The surface N content of BC increased more than 20 times by N-doping; meanwhile the content of oxidized-N was gradually diminished but graphitic-N was formed and increased with increasing annealing temperature and duration time. After N-doping, a high graphitic-N percentage (46.4%) and SBET (418.7 m(2)/g) can be achieved for BC. As a result, the N-doped BC exhibited an excellent adsorption capacity for Cu(2+) (1...
October 26, 2017: Chemosphere
Christin Glowa, Peter Peschke, Stephan Brons, Oliver C Neels, Klaus Kopka, Jürgen Debus, Christian P Karger
BACKGROUND: To summarize the research activities of the "clinical research group heavy ion therapy", funded by the German Research Foundation (DFG, KFO 214), on the impact of intrinsic tumor characteristics (grading, hypoxia) on local tumor control after carbon ((12)C-) ion- and photon irradiations. METHODS: Three sublines of syngeneic rat prostate tumors (R3327) with various differentiation levels (highly (-H), moderately (-HI) or anaplastic (-AT1), (diameter 10 mm) were irradiated with 1, 2 and 6 fractions of either (12)C-ions or 6 MV photons using increasing dose levels...
November 9, 2017: Radiation Oncology
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