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1Latest Papers from Table of Contents or Articles in PressC. A. Rietveld ; S. E. Medland ; J. Derringer ; J. Yang ; T. Esko ; N. W. Martin ; H. J. Westra ; K. Shakhbazov ; A. Abdellaoui ; A. Agrawal ; E. Albrecht ; B. Z. Alizadeh ; N. Amin ; J. Barnard ; S. E. Baumeister ; K. S. Benke ; L. F. Bielak ; J. A. Boatman ; P. A. Boyle ; G. Davies ; C. de Leeuw ; N. Eklund ; D. S. Evans ; R. Ferhmann ; K. Fischer ; C. Gieger ; H. K. Gjessing ; S. Hagg ; J. R. Harris ; C. Hayward ; C. Holzapfel ; C. A. Ibrahim-Verbaas ; E. Ingelsson ; B. Jacobsson ; P. K. Joshi ; A. Jugessur ; M. Kaakinen ; S. Kanoni ; J. Karjalainen ; I. Kolcic ; K. Kristiansson ; Z. Kutalik ; J. Lahti ; S. H. Lee ; P. Lin ; P. A. Lind ; Y. Liu ; K. Lohman ; M. Loitfelder ; G. McMahon ; P. M. Vidal ; O. Meirelles ; L. Milani ; R. Myhre ; M. L. Nuotio ; C. J. Oldmeadow ; K. E. Petrovic ; W. J. Peyrot ; O. Polasek ; L. Quaye ; E. Reinmaa ; J. P. Rice ; T. S. Rizzi ; H. Schmidt ; R. Schmidt ; A. V. Smith ; J. A. Smith ; T. Tanaka ; A. Terracciano ; M. J. van der Loos ; V. Vitart ; H. Volzke ; J. Wellmann ; L. Yu ; W. Zhao ; J. Allik ; J. R. Attia ; S. Bandinelli ; F. Bastardot ; J. Beauchamp ; D. A. Bennett ; K. Berger ; L. J. Bierut ; D. I. Boomsma ; U. Bultmann ; H. Campbell ; C. F. Chabris ; L. Cherkas ; M. K. Chung ; F. Cucca ; M. de Andrade ; P. L. De Jager ; J. E. De Neve ; I. J. Deary ; G. V. Dedoussis ; P. Deloukas ; M. Dimitriou ; G. Eiriksdottir ; M. F. Elderson ; J. G. Eriksson ; D. M. Evans ; J. D. Faul ; L. Ferrucci ; M. E. Garcia ; H. Gronberg ; V. Guethnason ; P. Hall ; J. M. Harris ; T. B. Harris ; N. D. Hastie ; A. C. Heath ; D. G. Hernandez ; W. Hoffmann ; A. Hofman ; R. Holle ; E. G. Holliday ; J. J. Hottenga ; W. G. Iacono ; T. Illig ; M. R. Jarvelin ; M. Kahonen ; J. Kaprio ; R. M. Kirkpatrick ; M. Kowgier ; A. Latvala ; L. J. Launer ; D. A. Lawlor ; T. Lehtimaki ; J. Li ; P. Lichtenstein ; P. Lichtner ; D. C. Liewald ; P. A. Madden ; P. K. Magnusson ; T. E. Makinen ; M. Masala ; M. McGue ; A. Metspalu ; A. Mielck ; M. B. Miller ; G. W. Montgomery ; S. Mukherjee ; D. R. Nyholt ; B. A. Oostra ; L. J. Palmer ; A. Palotie ; B. W. Penninx ; M. Perola ; P. A. Peyser ; M. Preisig ; K. Raikkonen ; O. T. Raitakari ; A. Realo ; S. M. Ring ; S. Ripatti ; F. Rivadeneira ; I. Rudan ; A. Rustichini ; V. Salomaa ; A. P. Sarin ; D. Schlessinger ; R. J. Scott ; H. Snieder ; B. St Pourcain ; J. M. Starr ; J. H. Sul ; I. Surakka ; R. Svento ; A. Teumer ; H. Tiemeier ; F. J. van Rooij ; D. R. Van Wagoner ; E. Vartiainen ; J. Viikari ; P. Vollenweider ; J. M. Vonk ; G. Waeber ; D. R. Weir ; H. E. Wichmann ; E. Widen ; G. Willemsen ; J. F. Wilson ; A. F. Wright ; D. Conley ; G. Davey-Smith ; L. Franke ; P. J. Groenen ; M. Johannesson ; S. L. Kardia ; R. F. Krueger ; D. Laibson ; N. G. Martin ; M. N. Meyer ; D. Posthuma ; A. R. Thurik ; N. J. Timpson ; A. G. Uitterlinden ; C. M. van Duijn ; P. M. Visscher ; D. J. Benjamin ; D. Cesarini ; P. D. Koellinger
American Association for the Advancement of Science (AAAS)
Published 2013Staff ViewPublication Date: 2013-06-01Publisher: American Association for the Advancement of Science (AAAS)Print ISSN: 0036-8075Electronic ISSN: 1095-9203Topics: BiologyChemistry and PharmacologyComputer ScienceMedicineNatural Sciences in GeneralPhysicsKeywords: Cognition ; *Educational Status ; Endophenotypes ; Female ; Genetic Loci ; *Genome-Wide Association Study ; Humans ; Male ; Multifactorial Inheritance ; *Polymorphism, Single NucleotidePublished by: -
2Articles: DFG German National LicensesStaff View
ISSN: 0022-4545Topics: PsychologySociologyURL: -
3Articles: DFG German National LicensesStaff View
ISSN: 1368-0382Topics: Ethnic SciencesNotes: JOURNAL of the ANTHROPOLOGICAL SOCIETY OF LONDONURL: -
4Latest Papers from Table of Contents or Articles in PressStaff View
Publication Date: 2018-05-16Publisher: American Heart Association (AHA)Print ISSN: 1942-325XElectronic ISSN: 1942-3268Topics: MedicineKeywords: Electrophysiology, Atrial Fibrillation, Ion Channels/Membrane Transport, Functional GenomicsPublished by: -
5Latest Papers from Table of Contents or Articles in PressHsu, J., Gore-Panter, S., Tchou, G., Castel, L., Lovano, B., Moravec, C. S., Pettersson, G. B., Roselli, E. E., Gillinov, A. M., McCurry, K. R., Smedira, N. G., Barnard, J., Van Wagoner, D. R., Chung, M. K., Smith, J. D.
American Heart Association (AHA)
Published 2018Staff ViewPublication Date: 2018-03-16Publisher: American Heart Association (AHA)Print ISSN: 1942-325XElectronic ISSN: 1942-3268Topics: MedicineKeywords: Arrhythmias, Gene Expression & Regulation, Functional GenomicsPublished by: -
6Articles: DFG German National LicensesParker, M. R. ; Seale, D. ; Tsang, E. ; Barnard, J. A. ; Hossain, S. ; Richards, D. A. ; Watson, M. L.
[S.l.] : American Institute of Physics (AIP)
Published 1993Staff ViewISSN: 1089-7550Source: AIP Digital ArchiveTopics: PhysicsNotes: It is well established that magnetic interactions in particulate media and films can be assessed on the basis of the correlation between the normalized dc demagnetization remanence, Id(H), and the normalized isothermal remagnetization remanence, Ir(H). Departures of Henkel plots from the straight-line relationship of the Wohlfarth equation may be regarded as a measure of the strength of the intergranular field interactions in thin films. Delta-I plots are commonly used to manifest these interactions. These remanence techniques have been applied to both ordered and highly disordered (granular) sputtered multilayers of Co/Cu in which the giant magnetoresistance effect has been observed. Both the Henkel plots and the delta-I (MR) plots exhibit oscillatory characteristics, which correlate with magnetoresistance and critical field data. Figure 1 shows the amplitude of the delta-I plot as a function of Cu volume fraction in quasigranular Co/Cu films in good correlation with the amplitude of the giant MR effect. Similar results have been obtained even with relatively thick multilayers of Fe/Cu in which the giant MR is extremely weak. These results would seem to indicate that comprehensive remanence measurements involving Henkel and/or delta-I plots are effective in evaluating intergranular exchange coupling in giant MR film systems, given that these plots can be processed to provide quantitative interaction field data.Type of Medium: Electronic ResourceURL: -
7Articles: DFG German National LicensesWatson, M. L. ; Barnard, J. A. ; Hossain, S. ; Parker, M. R.
[S.l.] : American Institute of Physics (AIP)
Published 1993Staff ViewISSN: 1089-7550Source: AIP Digital ArchiveTopics: PhysicsNotes: We report the observation of a large magnetoresistance in as-deposited co-sputtered Ag-Ni-Fe films. The size of the magnetoresistance has been measured as a function of the film composition. Measurement of the samples' hysteresis indicates that smaller Ag concentrations result in regions of the films becoming ferromagnetically coupled while greater concentrations result in the formation of a superparamagnetic state. Crystallographic evidence obtained using x-ray diffraction shows the samples to have the crystal structure of a contracted Ag lattice possibly caused by the inclusion of Ni and Fe.Type of Medium: Electronic ResourceURL: -
8Articles: DFG German National LicensesParker, M. R. ; Barnard, J. A. ; Seale, D. ; Waknis, A.
[S.l.] : American Institute of Physics (AIP)
Published 1993Staff ViewISSN: 1089-7550Source: AIP Digital ArchiveTopics: PhysicsNotes: Giant magnetoresistance in granular alloy thin films prepared by co-sputtering as well as in quasi-granular disordered multilayers has been modeled with relative ease using a simple scattering concept appropriate to superparamagnetic films and involving the Langevin function. The model has been applied to both as-deposited and annealed samples with the result that approximate sizes of spin clusters may be determined.Type of Medium: Electronic ResourceURL: -
9Articles: DFG German National LicensesBarnard, J. A. ; Hossain, S. ; Parker, M. R. ; Waknis, A. ; Watson, M. L.
[S.l.] : American Institute of Physics (AIP)
Published 1993Staff ViewISSN: 1089-7550Source: AIP Digital ArchiveTopics: PhysicsNotes: "Giant'' magnetoresistance ratios have been measured at room temperature in single layer Co–Ag alloy thin film. The effect has been observed over a broad range of Co concentrations with a maximum as-deposited MR ratio of ≥22% (at x=0.38). The effects of two annealing sequences have also been studied. The MR ratio generally increases on annealing reaching a maximum of ∼28% (at x=0.38) after the second anneal.Type of Medium: Electronic ResourceURL: -
10Articles: DFG German National LicensesStaff View
ISSN: 1089-7550Source: AIP Digital ArchiveTopics: PhysicsNotes: High-power density, high growth rate dc magnetron reactive sputtering has been used to grow single-layer FeTaN films. Ta has been found effective in improving the soft magnetic properties as well as the thermal stability of FeN films. For films containing ∼1.6 a/o Ta prepared under sputtering conditions of pN2/pAr=0.06, a power density of 2.5 or 3.9 W/cm2 and vacuum post-annealed at 350 °C for 1 h, the following properties are observed: saturation magnetization (Ms) values of ∼1550 emu/cc, coercivity (Hc) of ∼1 Oe, permeability of 1700–2300 at 20 MHz, and anisotropy field of ∼7 Oe. XRD scans yielded peaks characteristic of a random polycrystalline single phase bcc structure.Type of Medium: Electronic ResourceURL: -
11Articles: DFG German National LicensesHaftek, E. ; Tan, M. ; Waknis, A. ; Barnard, J. A.
[S.l.] : American Institute of Physics (AIP)
Published 1991Staff ViewISSN: 1089-7550Source: AIP Digital ArchiveTopics: PhysicsNotes: A series of periodic multilayer Ti/Ni thin films of the form (xTi/yNi)n were grown at room temperature by alternate deposition of elemental Ti and Ni onto glass substrates using dc-magnetron sputtering. The thicknesses of the individual Ti and Ni layers are given by x and y, respectively, and the total number of bilayer units is n. For this set of experiments, x was fixed at 2.8 nm while y was systematically varied from 2.4 to 154 nm. The product ny was held constant for all samples so that each film contained the same quantity of Ni. The growth rates of Ti and Ni were 0.14 and 0.32 nm/s, respectively. The multilayers were tested in the as-deposited state for magnetic properties using a vibrating sample magnetometer. These superlattices showed a variety of magnetic characteristics which were dependent on the thickness of the Ni layers. The coercivity of the multilayers declined with Ni layer thickness from a maximum of 80 Oe to a minimum of 7 Oe. A systematic reduction in saturation magnetization (Ms) with Ni layer thickness was also observed (for multilayers with y〈38 nm). In order to determine if the reduction in Ms could be attributed to a specific structural feature, a systematic study using transmission electron microscopy (imaging and electron diffraction) was made of the individual Ti/Ni and Ni/Ti bilayer units which comprise the superlattices. The bilayer units were grown under the same sputtering conditions used for the multilayers. Evidence was found for substantial strain (+4%) in the Ni layers and for the formation of Ni-Ti compounds presumably nucleated at the interfaces (the extra electron diffraction rings most closely match Ni3Ti).Type of Medium: Electronic ResourceURL: -
12Articles: DFG German National LicensesBarnard, J. A. ; Tan, M. ; Waknis, A. ; Haftek, E.
[S.l.] : American Institute of Physics (AIP)
Published 1991Staff ViewISSN: 1089-7550Source: AIP Digital ArchiveTopics: PhysicsNotes: Periodic multilayer thin films of the form (xAl/yFe-N)n were grown by sequential dc-magnetron sputtering. The thicknesses of the individual Al and Fe-N layers are given by x and y, respectively, and the total number of bilayer units is n. For this set of experiments, x was fixed at 3.5 nm and y was varied systematically from 3 to 135 nm. Magnetic properties were studied by vibrating sample magnetometry and crystal structure by x-ray diffraction for both as-deposited and annealed films. A strong enhancement of the saturation magnetization was found in multilayers containing the thinnest Fe-N layers which was further strengthened by annealing. The coercivity was found to decline monotonically with decreasing Fe-N layer thickness in the as-deposited films. Annealing produced nonsystematic changes in coercivity. The evolution of magnetic properties with decreasing Fe-N layer thickness was correlated with complex changes in iron-nitride crystal structure. For the thinnest layers of Fe-N (less than 12 nm) the multilayers exhibited an essentially amorphous structure.Type of Medium: Electronic ResourceURL: -
13Articles: DFG German National LicensesYan, B. D. ; Warren, G. W. ; Kim, M. H. ; Barnard, J. A.
[S.l.] : American Institute of Physics (AIP)
Published 1990Staff ViewISSN: 1089-7550Source: AIP Digital ArchiveTopics: PhysicsNotes: A series of GdxTby(Fe92Co8)100-x-y alloy thin films (about 200 nm in thickness) on glass substrates was prepared by dc magnetron sputtering using composite targets of pure Fe, Tb, Gd, and Co. Film composition was changed by varying the area percent of Tb and Gd in the target from 0% to 24%. In order to study the individual and combined effects of Gd and Tb, alloys of GdFeCo, TbFeCo, and GdTbFeCo were compared to each other and to an Fe92Co8 alloy. These comparisons were made on the basis of standard electrochemical tests, including anodic polarization as well as measurement of open circuit potentials and potential decay, in deaerated 0.15-M NaH2PO4 buffer solution (pH=4) at 25 °C. Results indicate that additions of Gd and Tb decrease the corrosion current of the Fe92Co8 alloy by a factor of 10 or more. Both Gd and Tb show very similar effects on the corrosion behavior of FeCo. Results suggest that a total of about 24% Gd and/or Tb may represent an optimum level for improving the corrosion resistance of GdTbFeCo magneto-optical thin films.Type of Medium: Electronic ResourceURL: -
14Articles: DFG German National LicensesWeston, J. L. ; Yan, S.-S. ; Zangari, G. ; Barnard, J. A.
[S.l.] : American Institute of Physics (AIP)
Published 2001Staff ViewISSN: 1089-7550Source: AIP Digital ArchiveTopics: PhysicsNotes: FeSm/FeTaN hard/soft multilayers with well-defined in-plane uniaxial anisotropy have been grown. Exchange spring behavior is observed and its occurrence and character is correlated with component layer thicknesses and volume fractions. The dc demagnetization remanence technique is used to determine the irreversible changes in the magnetization of the exchange spring structure. © 2001 American Institute of Physics.Type of Medium: Electronic ResourceURL: -
15Articles: DFG German National LicensesStaff View
ISSN: 1089-7550Source: AIP Digital ArchiveTopics: PhysicsNotes: In this study 2000 Å FeTaN thin films are annealed at 150 °C in both longitudinal and transverse magnetic fields. Both anneals result in a decrease in HK, which is shown to be a result of interstitial N, however, the transverse anneal results in a 90° rotation of HK and a 33% larger decrease in the magnitude of HK as compared to the longitudinal anneal. Subsequent transverse field anneals show that HK is completely reversible in relatively short times at any temperature above 75 °C. Our results are consistent with the diffusion of interstitial N being responsible for the rotatable behavior of HK in FeTaN. © 1999 American Institute of Physics.Type of Medium: Electronic ResourceURL: -
16Articles: DFG German National LicensesZhou, J. N. ; Rar, A. ; Otte, D. ; Barnard, J. A.
[S.l.] : American Institute of Physics (AIP)
Published 2000Staff ViewISSN: 1089-7550Source: AIP Digital ArchiveTopics: PhysicsNotes: The adhesion of an ultrathin carbon nitride (CN) coating to the surface of a two-phase CoPt–SiO2 granular film heterogeneous at the 10 nm scale has been studied using nanoscratch techniques. The nanoscratch resistance was found to depend sensitively on the volume fraction of the two phases. Both nanoscratch experiments and complementary electron microscopy observations indicate that CN adheres much more strongly to the SiO2 matrix than to the CoPt granules resulting in enhanced tribological performance in SiO2-rich films. The relative weakness of the CN/CoPt interface is correlated to the absence of interfacial metal nitride formation. The adhesion of the CN coating to the granular surface, the intrinsic mechanical properties of the underlying granular film (nanoindentation hardness and modulus), and the vertical rms surface roughness of the granular layer are all fundamentally changed as the CoPt content reaches the percolation threshold. © 2000 American Institute of Physics.Type of Medium: Electronic ResourceURL: -
17Articles: DFG German National LicensesLiu, F. ; Umlor, M. T. ; Shen, L. ; Weston, J. ; Eads, W. ; Barnard, J. A. ; Mankey, G. J.
[S.l.] : American Institute of Physics (AIP)
Published 1999Staff ViewISSN: 1089-7550Source: AIP Digital ArchiveTopics: PhysicsNotes: Chiral nanostructured thin films can be produced through precise control of the angle of incidence of a vapor flux concurrent with substrate rotation. The technique has been employed to create unique porous iron thin film structures on Si(100) with a columnar microstructure. Scanning electron microscopy images illustrate columnar iron films produced with azimuthal rotation during sample growth with the incident flux at an angle of 75° with respect to the surface normal. The columns were found to be well isolated with a narrow distribution of diameters, resulting in aspect ratios of approximately 8 to 1. Hysteresis loops reveal the columnar growth induced a large magnetic shape anisotropy relative to that observed for an iron film grown with normal incidence. The evolution of the columnar microstructure was followed from simple oblique deposition (no substrate rotation), giving a fibrous slanted microstructure, to high-speed rotation where a broad size distribution of highly faceted columnar structures was observed. The measured microstructure is related to the observed magnetic properties. © 1999 American Institute of Physics.Type of Medium: Electronic ResourceURL: -
18Articles: DFG German National LicensesViala, B. ; Minor, M. K. ; Barnard, J. A.
[S.l.] : American Institute of Physics (AIP)
Published 1996Staff ViewISSN: 1089-7550Source: AIP Digital ArchiveTopics: PhysicsNotes: As-deposited, magnetically soft nanocrystalline FeTaN films are successfully grown by dc-magnetron reactive sputtering. Growth conditions are instrumental in extending the solubility limit of Ta in the bcc FeTa alloy. Nitrogen incorporation in FeTa films is found to be much higher than in Fe films and can be explained in terms of thermochemistry using a large Ta-N interaction coefficient. The influence of different alloying elements is discussed theoretically, with regard to the metal-nitrogen affinity. A "typical columnar microstructure'' associated with the sputtering process is identified and its evolution versus the extent of nitrogenation is described in detail. Stress, magnetostriction, resistivity, and magnetic properties are respectively described as a function of both Ta and N contents of the films. The magnetic behavior of as-deposited nanocrystalline FeTaN is found to be very sensitive to both the dimension of the grains, their morphology and the nature of the grain boundary material which represents a non-negligible volume fraction in nanocrystalline films. It is proposed that the columnar structure plays the key role in promoting a large perpendicular anisotropy component (K⊥) and controls a "Stripe Domain''-like behavior observed at high N contents, which cannot be explained in terms of film stress in this material. The contribution of the magnetoelastic anisotropy is also described. In summary, by breaking the columnar structure, the incorporation of nitrogen first decreases K⊥ below the critical limit for formation of stripe domains. In these conditions, N acts as a "grain refiner'' and excellent soft magnetic behavior is reported and explained in terms of "vanishing magnetocrystalline anisotropy.'' The good thermal stability of such soft films is confirmed. By contrast, higher nitrogen incorporation increases K⊥ above the critical limit, leading to a stable stripe domain-like structure which does not allow for soft magnetic properties. This phenomenon has been found to be reversible at low temperature where a complete restoration of the soft magnetic behavior has been observed. This anomalous result is explained by the transformation of the grain boundary material into a "low Curie temperature phase'' for large N contents. © 1996 American Institute of Physics.Type of Medium: Electronic ResourceURL: -
19Articles: DFG German National LicensesStaff View
ISSN: 1089-7550Source: AIP Digital ArchiveTopics: PhysicsNotes: The thermal evolution of structure, giant magnetoresistance (GMR), and magnetic properties in two sequences of sputtered (Co90Fe10/Ag) multilayers is presented. Granular-type and "discontinuous'' GMR is observed depending on layer thickness. © 1996 American Institute of Physics.Type of Medium: Electronic ResourceURL: -
20Articles: DFG German National LicensesMinor, M. K. ; Viala, B. ; Barnard, J. A.
[S.l.] : American Institute of Physics (AIP)
Published 1996Staff ViewISSN: 1089-7550Source: AIP Digital ArchiveTopics: PhysicsNotes: Domain structures in thin-film heads can be significantly influenced by magnetoelastic anisotropy. In this study we have undertaken systematic measurements of magnetostriction and stress in as-deposited and annealed states in FeN and FeTaN single-layer thin films with varying nitrogen contents. Magnetostriction was positive for FeN films, increased with increasing nitrogen content, and shifted toward negative values after annealing. Stress in as-deposited FeN films was tensile and decreased (became more compressive) with increasing nitrogen content. Annealing the FeN films resulted in significant stress relief. By contrast, magnetostriction was found to be negative for simple FeTa (zero nitrogen) and increased linearly with increasing nitrogen content to positive values. The magnetostriction in FeTaN did not change significantly after annealing at 200 and 250 °C. FeTaN film stresses were compressive in the as-deposited state and increased in magnitude (became more compressive) with increasing nitrogen content. After annealing these stresses were relieved slightly. Ta has been found to be very effective in enhancing the thermal stability of the FeN films. © 1996 American Institute of Physics.Type of Medium: Electronic ResourceURL: