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Records |
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Author |
Shi, P.; Chen, L.; Quinn, B.K.; Yu, K.; Miao, Q.; Guo, X.; Lian, M.; Gielis, J.; Niklas, K.J. |
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Title |
A simple way to calculate the volume and surface area of avian eggs |
Type |
A1 Journal article |
| |
Year |
2023 |
Publication |
Annals of the New York Academy of Sciences |
Abbreviated Journal |
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| |
Volume  |
1524 |
Issue |
1 |
Pages |
118-131 |
| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL) |
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Abstract |
Egg geometry can be described using Preston's equation, which has seldom been used to calculate egg volume (V) and surface area (S) to explore S versus V scaling relationships. Herein, we provide an explicit re-expression of Preston's equation (designated as EPE) to calculate V and S, assuming that an egg is a solid of revolution. The side (longitudinal) profiles of 2221 eggs of six avian species were digitized, and the EPE was used to describe each egg profile. The volumes of 486 eggs from two avian species predicted by the EPE were compared with those obtained using water displacement in graduated cylinders. There was no significant difference in V using the two methods, which verified the utility of the EPE and the hypothesis that eggs are solids of revolution. The data also indicated that V is proportional to the product of egg length (L) and maximum width (W) squared. A 2/3-power scaling relationship between S and V for each species was observed, that is, S is proportional to (LW2)(2/3). These results can be extended to describe the shapes of the eggs of other species to study the evolution of avian (and perhaps reptilian) eggs. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000975679400001 |
Publication Date |
2023-04-28 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0077-8923; 1749-6632 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
5.2 |
Times cited |
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Open Access |
OpenAccess |
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Notes |
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Approved |
Most recent IF: 5.2; 2023 IF: 4.706 |
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Call Number |
UA @ admin @ c:irua:196724 |
Serial |
8827 |
| Permanent link to this record |
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Author |
Zarenia, M.; Vasilopoulos, P.; Pourtolami, N.; Peeters, F.M. |
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Title |
Landau-level dispersion and the quantum Hall plateaus in bilayer graphene |
Type |
P1 Proceeding |
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Year |
2013 |
Publication |
AIP conference proceedings |
Abbreviated Journal |
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Volume |
1566 |
Issue |
|
Pages |
275-276 |
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Keywords |
P1 Proceeding; Condensed Matter Theory (CMT) |
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Abstract |
We study the quantum Hall effect (QHE) in bilayer graphene using the Kubo-Greenwood formula. At zero temperature the Hall conductivity sigma(yx) is given by sigma(yx) – 4(N + 1)e(2)/h with N the index of the highest occupied Landau level (LL). Including the dispersion of the LLs and their width, due to e. g. scattering by impurities, produces the plateau of the n = 0 LL in agreement with experimental results on doped samples and similar theoretical results on single-layer graphene plateaus widen with impurity concentration. Further, the evaluated resistivity rho(xx) exhibits a strong, oscillatory dependence on the electron concentration. Explicit results are obtained for delta-function impurities. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
New York |
Editor |
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Language |
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Wos |
000331793000137 |
Publication Date |
2014-01-03 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
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ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
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Times cited |
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Open Access |
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Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl), the European Science Foundation (project CONGRAN) and the Canadian NSERC Grant No. OGP0121756. ; |
Approved |
Most recent IF: NA |
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Call Number |
UA @ lucian @ c:irua:115871 |
Serial |
1770 |
| Permanent link to this record |
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Author |
Borhani, A.H.; Berghmans, H.; Trashin, S.; De Wael, K.; Fago, A.; Moens, L.; Habibi-Rezaei, M.; Dewilde, S. |
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Title |
Kinetic properties and heme pocket structure of two domains of the polymeric hemoglobin of Artemia in comparison with the native molecule |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
Biochimica et biophysica acta : proteins and proteomics |
Abbreviated Journal |
Bba-Proteins Proteom |
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Volume |
1854 |
Issue |
10a |
Pages |
1307-1316 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
In this project, we studied some physicochemical properties of two different globin domains of the polymeric hemoglobin of the brine shrimp Artemia salina and compared them with those of the native molecule. Two domains (AsHbC1D1 and AsHbC1D5) were cloned and expressed in BL21(DE3)pLysS strain of Escherichiacoli. The recombinant proteins as well as the native hemoglobin (AfHb) were purified from bacteria and frozen Artemia, respectively by standard chromatographic methods and assessed by SDS-PAGE. The heme environment of these proteins was studied by optical spectroscopy and ligand-binding kinetics (e.g. CO association and O2 binding affinity) were measured for the two recombinant proteins and the native hemoglobin. This indicates that the CO association rate for AsHbC1D1 is higher than that of AsHbC1D5 and AfHb, while the calculated P50 value for AsHbC1D1 is lower than that of AsHbC1D5 and AfHb. The geminate and bimolecular rebinding parameters indicate a significant difference between both domains. Moreover, EPR results showed that the heme pocket in AfHb is in a more closed conformation than the heme pocket in myoglobin. Finally, the reduction potential of − 0.13 V versus the standard hydrogen electrode was determined for AfHb by direct electrochemical measurements. It is about 0.06 V higher than the potential of the single domain AsHbC1D5. This work shows that each domain in the hemoglobin of Artemia has different characteristics of ligand binding. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000362307500008 |
Publication Date |
2015-05-22 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
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ISSN |
1570-9639 |
ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
2.773 |
Times cited |
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Open Access |
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Notes |
; This work was supported by the general grant for visiting scholar of the Ministry of Science, Research and Technology of I. R. Iran and by the University of Antwerp. ; |
Approved |
Most recent IF: 2.773; 2015 IF: 2.747 |
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Call Number |
UA @ admin @ c:irua:125909 |
Serial |
5683 |
| Permanent link to this record |
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Author |
Yusupov, M.; Van der Paal, J.; Neyts, E.C.; Bogaerts, A. |
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Title |
Synergistic effect of electric field and lipid oxidation on the permeability of cell membranes |
Type |
A1 Journal article |
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Year |
2017 |
Publication |
Biochimica et biophysica acta : G : general subjects |
Abbreviated Journal |
Bba-Gen Subjects |
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Volume |
1861 |
Issue |
1861 |
Pages |
839-847 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
Background: Strong electric fields are knownto affect cell membrane permeability,which can be applied for therapeutic purposes, e.g., in cancer therapy. A synergistic enhancement of this effect may be accomplished by the presence of reactive oxygen species (ROS), as generated in cold atmospheric plasmas. Little is known about the synergy between lipid oxidation by ROS and the electric field, nor on howthis affects the cell membrane permeability.
Method: We here conduct molecular dynamics simulations to elucidate the dynamics of the permeation process under the influence of combined lipid oxidation and electroporation. A phospholipid bilayer (PLB), consisting of di-oleoyl-phosphatidylcholine molecules covered with water layers, is used as a model system for the plasma membrane.
Results and conclusions:Weshow howoxidation of the lipids in the PLB leads to an increase of the permeability of the bilayer to ROS, although the permeation free energy barriers still remain relatively high. More importantly, oxidation of the lipids results in a drop of the electric field threshold needed for pore formation (i.e., electroporation) in the PLB. The created pores in the membrane facilitate the penetration of reactive plasma species deep into the cell interior, eventually causing oxidative damage.
General significance: This study is of particular interest for plasma medicine, as plasma generates both ROS and electric fields, but it is also of more general interest for applications where strong electric fields and ROS both come into play. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000397366200012 |
Publication Date |
2017-01-27 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0304-4165 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.702 |
Times cited |
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Open Access |
OpenAccess |
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Notes |
This work is financially supported by the Fund for Scientific Research Flanders (FWO; grant numbers: 1200216N and 11U5416N). The work was carried out using the Turing HPC infrastructure of the CalcUA core facility of the Universiteit Antwerpen, a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flem |
Approved |
Most recent IF: 4.702 |
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Call Number |
PLASMANT @ plasmant @ c:irua:140095 |
Serial |
4413 |
| Permanent link to this record |
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Author |
Meilikhov, M.; Yusenko, K.; Esken, D.; Turner, S.; Van Tendeloo, G.; Fischer, R.A. |
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Title |
Metals@MOFs – loading MOFs with metal nanoparticles for hybrid functions |
Type |
A1 Journal article |
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Year |
2010 |
Publication |
European journal of inorganic chemistry |
Abbreviated Journal |
Eur J Inorg Chem |
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Volume |
2010 |
Issue |
24 |
Pages |
3701-3714 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Metalorganic frameworks (MOFs) as well as porous coordination polymers (PCPs) are porous, organicinorganic hybrid solids with zeolite-like structures and properties. Due to their extraordinarily high surface area and well defined pore structure MOFs can be used for the stabilization of metal nanoparticles with adjustable size. The embedded metal nanoparticles are still accessible for other reagents due to the high porosity of the MOF systems. This fact makes metal@MOF systems especially interesting for heterogeneous catalysis, gas storage and chemical sensing. This review compiles the cases of metal nanoparticles supported by or embedded into MOFs reported so far and the main aspects and problems associated with these novel nanocomposite systems. The determination of the dispersion and the location of the particles at the MOF support, the control of the loading degree and its effect on the catalytic activity of the system are discussed as well as the partial degradation of the MOF structure upon particle formation. Examples of the introduction of stabilizing groups into the MOF network that direct the loading and can influence the size and shape of the embedded particles are still rare and point into the possible direction of future investigations. Finally, the formation of bimetallic nanoparticles, which are stabilized and supported by a MOF network, will also be reviewed. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Weinheim |
Editor |
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Language |
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Wos |
000281684300001 |
Publication Date |
2010-07-09 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1434-1948; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.444 |
Times cited |
366 |
Open Access |
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Notes |
Esteem 026019 |
Approved |
Most recent IF: 2.444; 2010 IF: 2.910 |
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Call Number |
UA @ lucian @ c:irua:85495 |
Serial |
2014 |
| Permanent link to this record |
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Author |
Yusupov, M.; Razzokov, J.; Cordeiro, R.M.; Bogaerts, A. |
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Title |
Transport of Reactive Oxygen and Nitrogen Species across Aquaporin: A Molecular Level Picture |
Type |
A1 Journal article |
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Year |
2019 |
Publication |
Oxidative medicine and cellular longevity |
Abbreviated Journal |
Oxid Med Cell Longev |
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Volume |
2019 |
Issue |
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Pages |
1-11 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
Aquaporins (AQPs) are transmembrane proteins that conduct not only water molecules across the cell membrane but also other solutes, such as reactive oxygen and nitrogen species (RONS), produced (among others) by cold atmospheric plasma (CAP). These RONS may induce oxidative stress in the cell interior, which plays a role in cancer treatment. The underlying mechanisms of the transport of RONS across AQPs, however, still remain obscure. We apply molecular dynamics simulations to investigate the permeation of both hydrophilic (H<sub>2</sub>O<sub>2</sub>and OH) and hydrophobic (NO<sub>2</sub>and NO) RONS through AQP1. Our simulations show that these RONS can all penetrate across the pores of AQP1. The permeation free energy barrier of OH and NO is lower than that of H<sub>2</sub>O<sub>2</sub>and NO<sub>2</sub>, indicating that these radicals may have easier access to the pore interior and interact with the amino acid residues of AQP1. We also study the effect of RONS-induced oxidation of both the phospholipids and AQP1 (i.e., sulfenylation of Cys<sub>191</sub>) on the transport of the above-mentioned RONS across AQP1. Both lipid and protein oxidation seem to slightly increase the free energy barrier for H<sub>2</sub>O<sub>2</sub>and NO<sub>2</sub>permeation, while for OH and NO, we do not observe a strong effect of oxidation. The simulation results help to gain insight in the underlying mechanisms of the noticeable rise of CAP-induced RONS in cancer cells, thereby improving our understanding on the role of AQPs in the selective anticancer capacity of CAP. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000492999000001 |
Publication Date |
2019-06-17 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1942-0900 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.593 |
Times cited |
5 |
Open Access |
OpenAccess |
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Notes |
The authors acknowledge the Turing HPC infrastructure at the CalcUA core facility of the University of Antwerp (UA), a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish Government (department EWI), and the UA, where all computational work was performed. M.Y. gratefully acknowledges Dr. U. Khalilov for the fruitful discussions. This work was financially supported by the Research Foundation Flanders (FWO) (grant number 1200219N). |
Approved |
Most recent IF: 4.593 |
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Call Number |
PLASMANT @ plasmant @UA @ admin @ c:irua:160118 |
Serial |
5180 |
| Permanent link to this record |
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Author |
Joosten, F.; Parrilla, M.; van Nuijs, A.L.N.; Ozoemena, K.Id; De Wael, K. |
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Title |
Electrochemical detection of illicit drugs in oral fluid : potential for forensic drug testing |
Type |
A1 Journal article |
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Year |
2022 |
Publication |
Electrochimica acta |
Abbreviated Journal |
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Volume |
2022 |
Issue |
436 |
Pages |
141309-141315 |
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Keywords |
A1 Journal article; Pharmacology. Therapy; Engineering sciences. Technology; Toxicological Centre; Antwerp Electrochemical and Analytical Sciences Lab (A-Sense Lab) |
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Abstract |
Illicit drugs continue to pose a serious threat to society and public health. Drug (ab)use is linked to organised crime and violence. Therefore, to fight the so-called war on drugs, police and law enforcement agencies need to be equipped with accurate and efficient sensors for the detection of illicit drugs and drug use. Even though colour tests (for powders) and lateral flow immunoassays (for biological samples) lack accuracy, they are relied upon for fast and easy on-site detection. Alternatively, in recent years, there has been an increasing interest in electrochemical sensors as a promising technique for the rapid and accurate on-site detection of illicit drugs. While a myriad of literature exists on the use of electrochemical sensors for drug powder analysis, literature on their use for the detection of drug use in biological samples is scarce. To this end, this review presents an overview of strategies for the electrochemical detection of illicit drugs in oral fluid. First, pharmacokinetics of drugs in oral fluid and the legal limit dilemma regarding the analytical cut-offs for roadside drug detection tests are elaborated to present the reader with the background knowledge required to develop such a test. Subsequently, an overview of electrochemical strategies developed for the detection of illicit drugs in oral fluid is given. Importantly, key challenges to address in the development of roadside tests are highlighted to improve the design of the next electrochemical devices and to bring them to the field. Overall, electrochemical sensors for illicit drugs detection in oral fluid show promise to disrupt current strategies for roadside testing. |
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Corporate Author |
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Place of Publication |
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Language |
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Wos |
000882442300001 |
Publication Date |
2022-10-13 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0013-4686 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
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Times cited |
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Open Access |
OpenAccess |
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Notes |
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Approved |
no |
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Call Number |
UA @ admin @ c:irua:191107 |
Serial |
8855 |
| Permanent link to this record |
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Author |
Lugli, L.F.; Fuchslueger, L.; Vallicrosa, H.; Van Langenhove, L.; Ranits, C.; Garberi, P.R.F.; Verryckt, L.; Grau, O.; Brechet, L.; Peguero, G.; Llusia, J.; Ogaya, R.; Marquez, L.; Portillo-Estrada, M.; Ramirez-Rojas, I.; Courtois, E.; Stahl, C.; Sardans, J.; Penuelas, J.; Verbruggen, E.; Janssens, I. |
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Title |
Contrasting responses of fine root biomass and traits to large-scale nitrogen and phosphorus addition in tropical forests in the Guiana shield |
Type |
A1 Journal article |
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Year |
2024 |
Publication |
Oikos: a journal of ecology |
Abbreviated Journal |
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Volume |
2024 |
Issue |
4 |
Pages |
e10412-14 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Plant and Ecosystems (PLECO) – Ecology in a time of change |
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Abstract |
Fine roots mediate plant nutrient acquisition and growth. Depending on soil nutrient availability, plants can regulate fine root biomass and morphological traits to optimise nutrient acquisition. Little is known, however, about the importance of these parameters influencing forest functioning. In this study, we measured root responses to nutrient additions to gain a mechanistic understanding of plant adaptations to nutrient limitation in two tropical forests in French Guiana, differing twofold in their soil nutrient statuses. We analysed the responses of root biomass, mean root diameter (RD), specific root length (SRL), specific root area (SRA), root tissue density (RTD) and carbon (C), nitrogen (N) and phosphorus (P) concentrations in roots down to 15 cm soil depth after three years of N and P additions. At the lower-fertility site Paracou, no changes in root biomass or morphological traits were detected with either N or P addition, although P concentrations in roots increased with P addition. In the higher fertility site, Nouragues, root biomass and P concentrations in roots increased with P addition, with no changes in morphological traits. In contrast, N addition shifted root traits from acquisitive to more conservative by increasing RTD. A significant interaction between N and P in Nouragues pointed to stronger responses to P addition in the absence of N. Our results suggest that the magnitude and direction of root biomass and trait expression were regulated by soil fertility, corroborated by the response to N or P additions. At low fertility sites, we found lower plasticity in root trait expression compared to more fertile conditions, where N and P additions caused stronger and antagonistic responses. Identifying the exact role of mechanisms affecting root nutrient uptake in Amazon forests growing in different soils will be crucial to foresee if and how rapid global changes can affect their carbon allocation. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
001142552200001 |
Publication Date |
2024-01-16 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0030-1299 |
ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
3.4 |
Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: 3.4; 2024 IF: 4.03 |
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Call Number |
UA @ admin @ c:irua:202834 |
Serial |
9195 |
| Permanent link to this record |
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Author |
de Backer, J.W.; Vos, W.G.; Germonpré, P.; Salgado, R.; Parizel, P.M.; de Backer, W. |
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Title |
Clinical applications of image-based airway computational fluid dynamics: assessment of inhalation medication and endobronchial devices |
Type |
A3 Journal article |
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Year |
2009 |
Publication |
Proceedings of the Society of Photo-optical Instrumentation Engineers |
Abbreviated Journal |
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Volume |
7262 |
Issue |
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Pages |
72621p,1-72621p,9 |
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Keywords |
A3 Journal article; Condensed Matter Theory (CMT); Antwerp Surgical Training, Anatomy and Research Centre (ASTARC); Laboratory Experimental Medicine and Pediatrics (LEMP) |
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Abstract |
Computational fluid dynamics (CFD) is a technique that is used increasingly in the biomedical field. Solving the flow equations numerically provides a convenient way to assess the efficiency of therapies and devices, ranging from cardiovascular stents and heart valves to hemodialysis workflows. Also in the respiratory field CFD has gained increasing interest, especially through the combination of three dimensional image reconstruction which results in highend patient-specific models. This paper provides an overview of clinical applications of CFD through image based modeling, resulting from recent studies performed in our center. We focused on two applications: assessment of the efficiency of inhalation medication and analysis of endobronchial valve placement. In the first application we assessed the mode of action of a novel bronchodilator in 10 treated patients and 4 controls. We assessed the local volume increase and resistance change based on the combination of imaging and CFD. We found a good correlation between the changes in volume and resistance coming from the CFD results and the clinical tests. In the second application we assessed the placement and effect of one way endobronchial valves on respiratory function in 6 patients. We found a strong patientspecific result of the therapy where in some patients the therapy resulted in complete atelectasis of the target lobe while in others the lobe remained inflated. We concluded from these applications that CFD can provide a better insight into clinically relevant therapies. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
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Publication Date |
2009-02-27 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
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ISBN |
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Additional Links |
UA library record |
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Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: NA |
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Call Number |
UA @ lucian @ c:irua:79497 |
Serial |
374 |
| Permanent link to this record |
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Author |
Kalesaki, E.; Boneschanscher, M.P.; Geuchies, J.J.; Delerue, C.; Morais Smith, C.; Evers, W.H.; Allan, G.; Altantzis, T.; Bals, S.; Vanmaekelbergh, D. |
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Title |
Preparation and study of 2-D semiconductors with Dirac type bands due to the honeycomb nanogeometry |
Type |
P1 Proceeding |
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Year |
2014 |
Publication |
Proceedings of the Society of Photo-optical Instrumentation Engineers
T2 – Proceedings of SPIE |
Abbreviated Journal |
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Volume |
8981 |
Issue |
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Pages |
898107-898107 |
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Keywords |
P1 Proceeding; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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Abstract |
The interest in 2-dimensional systems with a honeycomb lattice and related Dirac-type electronic bands has exceeded the prototype graphene1. Currently, 2-dimensional atomic2,3 and nanoscale4-8 systems are extensively investigated in the search for materials with novel electronic properties that can be tailored by geometry. The immediate question that arises is how to fabricate 2-D semiconductors that have a honeycomb nanogeometry, and as a consequence of that, display a Dirac-type band structure? Here, we show that atomically coherent honeycomb superlattices of rocksalt (PbSe, PbTe) and zincblende (CdSe, CdTe) semiconductors can be obtained by nanocrystal self-assembly and facet-to-facet atomic bonding, and subsequent cation exchange. We present a extended structural analysis of atomically coherent 2-D honeycomb structures that were recently obtained with self-assembly and facet-to-facet bonding9. We show that this process may in principle lead to three different types of honeycomb structures, one with a graphene type-, and two others with a silicene-type structure. Using TEM, electron diffraction, STM and GISAXS it is convincingly shown that the structures are from the silicene-type. In the second part of this work, we describe the electronic structure of graphene-type and silicene type honeycomb semiconductors. We present the results of advanced electronic structure calculations using the sp3d5s* atomistic tight-binding method10. For simplicity, we focus on semiconductors with a simple and single conduction band for the native bulk semiconductor. When the 3-D geometry is changed into 2-D honeycomb, a conduction band structure transformation to two types of Dirac cones, one for S- and one for P-orbitals, is observed. The width of the bands depends on the honeycomb period and the coupling between the nanocrystals. Furthermore, there is a dispersionless P-orbital band, which also forms a landmark of the honeycomb structure. The effects of considerable intrinsic spin-orbit coupling are briefly considered. For heavy-element compounds such as CdTe, strong intrinsic spin-‐orbit coupling opens a non-trivial gap at the P-orbital Dirac point, leading to a quantum Spin Hall effect10-12. Our work shows that well known semiconductor crystals, known for centuries, can lead to systems with entirely new electronic properties, by the simple action of nanogeometry. It can be foreseen that such structures will play a key role in future opto-electronic applications, provided that they can be fabricated in a straightforward way. |
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000336040600004 |
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2014-03-07 |
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UA library record; WoS full record; WoS citing articles |
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2 |
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OpenAccess |
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Notes |
This work has been supported by funding of the French National Research Agency [ANR, (ANR-‐09-‐BLAN-‐0421-‐01)], NWO and the Dutch organization FOM [Programs “Control over Functional Nanoparticle Solids” (FNPS) and “Designing Dirac Carriers in Semiconductors” |
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Most recent IF: NA |
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Call Number |
c:irua:131912 |
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4039 |
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