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1Latest Papers from Table of Contents or Articles in PressBenedict Anchang, Kara L. Davis, Harris G. Fienberg, Brian D. Williamson, Sean C. Bendall, Loukia G. Karacosta, Robert Tibshirani, Garry P. Nolan, Sylvia K. Plevritis
National Academy of Sciences
Published 2018Staff ViewPublication Date: 2018-05-02Publisher: National Academy of SciencesPrint ISSN: 0027-8424Electronic ISSN: 1091-6490Topics: BiologyMedicineNatural Sciences in GeneralPublished by: -
2Latest Papers from Table of Contents or Articles in PressD. T. Jones ; N. Jager ; M. Kool ; T. Zichner ; B. Hutter ; M. Sultan ; Y. J. Cho ; T. J. Pugh ; V. Hovestadt ; A. M. Stutz ; T. Rausch ; H. J. Warnatz ; M. Ryzhova ; S. Bender ; D. Sturm ; S. Pleier ; H. Cin ; E. Pfaff ; L. Sieber ; A. Wittmann ; M. Remke ; H. Witt ; S. Hutter ; T. Tzaridis ; J. Weischenfeldt ; B. Raeder ; M. Avci ; V. Amstislavskiy ; M. Zapatka ; U. D. Weber ; Q. Wang ; B. Lasitschka ; C. C. Bartholomae ; M. Schmidt ; C. von Kalle ; V. Ast ; C. Lawerenz ; J. Eils ; R. Kabbe ; V. Benes ; P. van Sluis ; J. Koster ; R. Volckmann ; D. Shih ; M. J. Betts ; R. B. Russell ; S. Coco ; G. P. Tonini ; U. Schuller ; V. Hans ; N. Graf ; Y. J. Kim ; C. Monoranu ; W. Roggendorf ; A. Unterberg ; C. Herold-Mende ; T. Milde ; A. E. Kulozik ; A. von Deimling ; O. Witt ; E. Maass ; J. Rossler ; M. Ebinger ; M. U. Schuhmann ; M. C. Fruhwald ; M. Hasselblatt ; N. Jabado ; S. Rutkowski ; A. O. von Bueren ; D. Williamson ; S. C. Clifford ; M. G. McCabe ; V. P. Collins ; S. Wolf ; S. Wiemann ; H. Lehrach ; B. Brors ; W. Scheurlen ; J. Felsberg ; G. Reifenberger ; P. A. Northcott ; M. D. Taylor ; M. Meyerson ; S. L. Pomeroy ; M. L. Yaspo ; J. O. Korbel ; A. Korshunov ; R. Eils ; S. M. Pfister ; P. Lichter
Nature Publishing Group (NPG)
Published 2012Staff ViewPublication Date: 2012-07-27Publisher: Nature Publishing Group (NPG)Print ISSN: 0028-0836Electronic ISSN: 1476-4687Topics: BiologyChemistry and PharmacologyMedicineNatural Sciences in GeneralPhysicsKeywords: Aging/genetics ; Amino Acid Sequence ; Cell Transformation, Neoplastic ; Cerebellar Neoplasms/classification/diagnosis/*genetics/pathology ; Child ; Chromatin/metabolism ; Chromosomes, Human/genetics ; DEAD-box RNA Helicases/genetics ; DNA Helicases/genetics ; DNA-Binding Proteins/genetics ; Genome, Human/*genetics ; Genomics ; Hedgehog Proteins/metabolism ; High-Throughput Nucleotide Sequencing ; Histone Demethylases/genetics ; Humans ; Medulloblastoma/classification/diagnosis/*genetics/pathology ; Methylation ; Mutation/genetics ; Mutation Rate ; Neoplasm Proteins/genetics ; Nuclear Proteins/genetics ; Oncogene Proteins, Fusion/genetics ; Phosphoprotein Phosphatases/genetics ; Polyploidy ; Receptors, Cell Surface/genetics ; Sequence Analysis, RNA ; Signal Transduction ; T-Box Domain Proteins/genetics ; Transcription Factors/genetics ; Wnt Proteins/metabolism ; beta Catenin/geneticsPublished by: -
3Latest Papers from Table of Contents or Articles in PressStaff View
Publication Date: 2018-10-16Publisher: Nature Publishing Group (NPG)Electronic ISSN: 2041-1723Topics: BiologyChemistry and PharmacologyNatural Sciences in GeneralPhysicsPublished by: -
4FIS Bildung LiteraturdatenbankStaff View
Type of Medium: bookPublication Date: 1994Keywords: Bilingualer Unterricht ; Fremdsprachenunterricht ; Englischunterricht ; Geschichtsunterricht ; Bismarck, Otto von ; Deutschland (bis 1945)Language: EnglishNote: Literaturangaben -
5Latest Papers from Table of Contents or Articles in PressWood, B., Wu, D., Crossley, B., Dai, Y., Williamson, D., Gawad, C., Borowitz, M. J., Devidas, M., Maloney, K. W., Larsen, E., Winick, N., Raetz, E., Carroll, W. L., Hunger, S. P., Loh, M. L., Robins, H., Kirsch, I.
American Society of Hematology (ASH)
Published 2018Staff ViewPublication Date: 2018-03-23Publisher: American Society of Hematology (ASH)Print ISSN: 0006-4971Electronic ISSN: 1528-0020Topics: BiologyMedicineKeywords: Pediatric Hematology, Free Research Articles, Lymphoid Neoplasia, Clinical Trials and ObservationsPublished by: -
6Latest Papers from Table of Contents or Articles in PressWilliamson, D. R., Dewan, K. K., Patel, T., Wastella, C. M., Ning, G., Kirimanjeswara, G. S.
The American Society for Microbiology (ASM)
Published 2018Staff ViewPublication Date: 2018-02-15Publisher: The American Society for Microbiology (ASM)Print ISSN: 0099-2240Electronic ISSN: 1098-5336Topics: BiologyPublished by: -
7Articles: DFG German National LicensesKopcewicz, Michal(Slashthrough accent mark) ; Jagielski, Jacek ; Turos, Andrzej ; Williamson, D. L.
[S.l.] : American Institute of Physics (AIP)
Published 1992Staff ViewISSN: 1089-7550Source: AIP Digital ArchiveTopics: PhysicsNotes: A systematic study of nitride-phase formation in iron implanted with nitrogen was performed by conversion electron Mössbauer spectroscopy (CEMS). The samples of α-iron were implanted at room temperature with 100 keV N+2 ions whose mean range in the iron target was about 55 nm. The implanted dose varied from 5×1016 to 6×1017 N atoms/cm2. After implantation each sample was isothermally annealed in vacuum for 1 h at temperatures from 150 to 500 °C in 50 °C steps. The CEMS measurements allowed identification of the iron nitride phases formed by implantation and after annealing. At low doses (up to 1.5×1017 N atoms/cm2), the nitrogen-containing α'-martensite and/or α‘-Fe16N2 phases appear. For intermediate doses (2×1017–2.7×1017 N atoms/cm2) ε-Fe3N is formed additionally. For doses higher than 3×1017 N atoms/cm2 the dominant phase is ε-Fe2N. In the course of annealing, ε-Fe2N decomposes to ε-Fe3N and γ'-Fe4N and finally disappears at about 300–350 °C. At 500 °C only the Zeeman sextet of α-Fe remains in the spectra. Considerable nitrogen release as detected by nuclear reaction analysis accompanied the phase evolution during annealing. These measurements lead to a new phase diagram for the implanted FeN system.Type of Medium: Electronic ResourceURL: -
8Articles: DFG German National LicensesCOTTERILL, J. A. ; CUNLIFFE, W. J. ; FORSTER, R. A. ; WILLIAMSON, D. M. ; BULUSU, L.
Oxford, UK : Blackwell Publishing Ltd
Published 1971Staff ViewISSN: 1365-2133Source: Blackwell Publishing Journal Backfiles 1879-2005Topics: MedicineType of Medium: Electronic ResourceURL: -
9Articles: DFG German National LicensesChattopadhyay, S. ; Sharma, S. N. ; Banerjee, Ratnabali ; Bhusari, D. M. ; Kshirsagar, S. T. ; Chen, Yan ; Williamson, D. L.
[S.l.] : American Institute of Physics (AIP)
Published 1994Staff ViewISSN: 1089-7550Source: AIP Digital ArchiveTopics: PhysicsNotes: Hydrogenated amorphous silicon (a-Si:H) films were deposited at high growth rates by increasing the rf power density in a (SiH4+H2) discharge, while powder formation due to gas phase polymerization was controlled by heating the cathode together with the anode. A combination of Raman scattering, infrared absorption, and small angle x-ray scattering experiments was used to study the short-range order and microstructure of films deposited in different (dusty or otherwise) plasma conditions. The results were correlated with initial and light-soaked photoresponse to demonstrate that films with more microstructure and less short-range order were generally poorer.Type of Medium: Electronic ResourceURL: -
10Articles: DFG German National LicensesLiou, J. J. ; Huang, C. I. ; Bayraktaroglu, B. ; Williamson, D. C. ; Parab, K. B.
[S.l.] : American Institute of Physics (AIP)
Published 1994Staff ViewISSN: 1089-7550Source: AIP Digital ArchiveTopics: PhysicsNotes: Base and collector leakage currents are extremely important to AlGaAs/GaAs heterojunction bipolar transistor (HBT) dc characteristics, and a simple model to describe such currents is presented. This study suggests that these currents are originated from the electron and hole leakage through the dielectric-layer (e.g., polyimide, nitride, etc.) interface at the emitter-base and base-collector peripheries, as well as through the n+-subcollector/semi-insulating substrate interface. Five HBTs having similar intrinsic make-ups (i.e., doping concentration and layer thickness) but different extrinsic make-ups (i.e., finger pattern, perimeter, dielectric layer, etc.) are investigated, and with the aid of the model, the possible mechanisms contributing to their leakage behavior identified.Type of Medium: Electronic ResourceURL: -
11Articles: DFG German National LicensesKopcewicz, M. ; Grabias, A. ; Nowicki, P. ; Williamson, D. L.
[S.l.] : American Institute of Physics (AIP)
Published 1996Staff ViewISSN: 1089-7550Source: AIP Digital ArchiveTopics: PhysicsNotes: The specialized technique of radio-frequency-induced collapse of Mössbauer spectra combined with conventional Mössbauer spectroscopy, x-ray diffraction (XRD), small-angle x-ray scattering (SAXS), and differential scanning calorimetry (DSC) are used to investigate in detail the magnetic and structural properties of the two magnetic materials Fe81Zr7B12 and Fe79Zr7B12Cu2. Thermal treatments to convert the as-quenched, fully amorphous state into mixtures of nanocrystalline and amorphous states and the effect of the small Cu addition were of primary interest due to the improved magnetic behavior in the mixed state. DSC shows that the Cu leads to a lowering of the onset temperature for formation of the nanocrystalline phase and also to an increase in the range of temperatures over which this phase forms. XRD and Mössbauer data show the nanoscale phase to be bcc Fe and the Mössbauer spectral parameters demonstrate it to be essentially pure Fe (i.e., with little or no Zr, B, or Cu substitutional impurities). The electron density contrast between the amorphous matrix and the bcc Fe permits the detection of the Fe grains by SAXS and significant volume fractions with sizes of only 2.8–8 nm are shown to exist. Larger sizes are also present as demonstrated by the XRD and Mössbauer data and a bimodal size distribution is suggested. The Mössbauer experiments in which the radio-frequency-induced effects (rf collapse and rf sidebands) are used, allows the nanocrystalline bcc phase to be distinguished from magnetically harder microcrystalline α-Fe. The complete rf collapse of the magnetic hyperfine structure occurs only in the amorphous and nanocrystalline phases and is suppressed by the formation of larger grains. The rf sidebands disappear when the nanocrystalline phase is formed, revealing that magnetostriction vanishes. The rf-Mössbauer studies are shown to be particularly sensitive to magnetic softness of the material in that large changes in the spectra are observed for applied field changes as small as 2 Oe. © 1996 American Institute of Physics.Type of Medium: Electronic ResourceURL: -
12Articles: DFG German National LicensesMiddya, A. R. ; Ray, Swati ; Jones, S. J. ; Williamson, D. L.
[S.l.] : American Institute of Physics (AIP)
Published 1995Staff ViewISSN: 1089-7550Source: AIP Digital ArchiveTopics: PhysicsNotes: The microstructures of two sets of hydrogenated amorphous silicon–germanium (a-Si1−xGex:H) alloys prepared by the plasma-enhanced, chemical-vapor-deposition technique with and without hydrogen dilution of the source gases (silane and germane) have been analyzed by small-angle x-ray scattering (SAXS), infrared vibrational spectroscopy, and flotation density measurements. Optoelectronic properties of codeposited films have also been characterized. Hydrogen dilution suppresses dihydride/polyhydride formation, reduces bonded H content, and reduces the SAXS-detected microstructure for x(approximately-greater-than)0. Studies of anisotropy in the SAXS intensity indicate an increased amount of oriented microstructure as Ge is added, consistent with a trend toward columnarlike growth in both undiluted and hydrogen-diluted films, but the diluted films have a significantly reduced degree of such oriented microstructure. The improvement in the microstructure of a-Si1−xGex:H films by H2 dilution correlates with concomitant improvement of optoelectronic properties. The modification of microstructure due to H2 dilution of the source gases is discussed in terms of growth mechanisms of alloy films. © 1995 American Institute of Physics.Type of Medium: Electronic ResourceURL: -
13Articles: DFG German National LicensesRensing, N. M. ; Clemens, B. M. ; Williamson, D. L.
[S.l.] : American Institute of Physics (AIP)
Published 1996Staff ViewISSN: 1089-7550Source: AIP Digital ArchiveTopics: PhysicsNotes: In previous work we reported that the magnetoresistance of Fe/Cr multilayers can be increased by annealing the films at moderate temperatures, which increases the spin-dependent scattering of the conduction electrons. Here we present Mössbauer data that demonstrate that the structural effect of annealing is to promote Cr interdiffusion into the bulk of the iron layers rather than short scale intermixing at the interfaces. We have also investigated the effect of increasing the asymmetric scattering by adding chromium to the iron in Fe/Cr multilayers. The additional Cr was either alloyed with the Fe in compositions ranging from 1.5% to 50% Cr in Fe, or concentrated into 1 or 2 A(ring) layers embedded at various positions in the Fe. We report enhanced room-temperature magnetoresistance of up to 11.4% in sputter-deposited Fe/Cr multilayers when the Fe layers are doped with 20% Cr. The maximum magnetoresistance observed for samples with embedded Cr layers was 10.5%. In comparison, the magnetoresistance was 7.5% in a similar, undoped sample. © 1996 American Institute of Physics.Type of Medium: Electronic ResourceURL: -
14Articles: DFG German National LicensesStaff View
ISSN: 1089-7550Source: AIP Digital ArchiveTopics: PhysicsNotes: The phase and composition depth distributions of a low-energy (0.7 keV), high-flux (2.5 mA/cm2) N implanted fcc AISI 304 stainless steel held at 400 °C have been investigated by step-wise Ar+ beam sputter removal in conjunction with conversion electron Mössbauer spectroscopy and x-ray diffraction (XRD). A metastable, fcc, high-N phase (γN), with both magnetic and paramagnetic characteristics, was found to be distributed in the N implanted layer generated by the low-energy, elevated temperature, implantation conditions. The magnetic γN was found to be ferromagnetic and was distributed in the highest N concentration region of the implanted layer (the top 0.5 μm) while the paramagnetic γN becomes predominant below 0.5 μm, where the N content is only slightly lower. The ferromagnetic state is linked to large lattice expansions due to high N contents (∼30 at.%) as determined by XRD and electron microprobe. The relatively uniform XRD N distribution to a depth of ∼1 μm suggests a sensitive dependence of the magnetic γN phase stability on N concentration and degree of lattice expansion. The XRD results also show that the N contents and depths depend on the polycrystalline grain orientation relative to the ion beam direction. The N was found to diffuse deeper in the (200) oriented polycrystalline grains compared to the (111) oriented grains and the N contents were significantly higher in the (200) planes relative to the (111) planes. The effect of compressive residual stresses (∼2 GPa) is considered. The scanning electron microscopy (SEM) analysis reveals quite clearly the uniform nature of the γN layers with a reasonably well defined interface between the γN layer and the substrate, suggesting uniform N contents with uniform layer thicknesses within a given grain. However, they also show significant variations in the γN layer thickness from one grain to the next along the N implanted layer, clearly supporting the XRD findings of the variation in N diffusivity with grain orientation. © 1995 American Institute of Physics.Type of Medium: Electronic ResourceURL: -
15Articles: DFG German National LicensesSheu, S. ; Liou, J. J. ; Huang, C. I. ; Williamson, D. C.
[S.l.] : American Institute of Physics (AIP)
Published 1996Staff ViewISSN: 1089-7550Source: AIP Digital ArchiveTopics: PhysicsNotes: The base current of AlGaAs/GaAs heterojunction bipolar transistor subjected to a long burn-in test often exhibits an abnormal characteristic with an ideality factor of about 3, rather than a normal ideality factor between 1 and 2, in the midvoltage range. We develope an analytical model to investigate the physical mechanisms underlying such a characteristic. Consistent with the finding of an experimental work reported recently, our model calculations show that the recombination current in the base has an ideality factor of about 3 in the midvoltage range and that such a current is responsible for the observed abnormal base current in heterojunction bipolar transistor after a long burn-in test. Post-burn-in data measured from two different heterojunction bipolar transistors are also included in support of the model. © 1996 American Institute of Physics.Type of Medium: Electronic ResourceURL: -
16Articles: DFG German National LicensesWilliamson, D. L. ; Mahan, A. H. ; Nelson, B. P. ; Crandall, R. S.
Woodbury, NY : American Institute of Physics (AIP)
Published 1989Staff ViewISSN: 1077-3118Source: AIP Digital ArchiveTopics: PhysicsNotes: The microstructure of hydrogenated amorphous silicon-carbon alloys has been analyzed by small-angle x-ray scattering, infrared absorption, and density measurements. Decreasing density with C incorporation is due to microvoids about 0.6 nm in average radius, which are either approximately spherical in shape or randomly oriented nonspheres. The microvoid number density increases from about 5×1019/cm3 for a-Si:H to about 4×1020/cm3 for a-Si0.7 C0.3 :H. The CH3 species probably causes the enhanced microvoid formation in these alloys. A large fraction of the microvoid surfaces is not hydrogenated.Type of Medium: Electronic ResourceURL: -
17Articles: DFG German National LicensesStaff View
ISSN: 1089-7550Source: AIP Digital ArchiveTopics: PhysicsNotes: Gallium arsenide single-crystal layers, doped with 119Sn-enriched tin, have been prepared by liquid-phase epitaxy and characterized by 119Sn Mössbauer spectroscopy (MS) and Hall measurements. Two Sn sites are observed by MS, and the population of one of these (site A) matches the carrier concentration in as-grown material, therefore allowing the MS parameters of this site to be positively identified as those of the SnGa donor in GaAs, and thereby showing no evidence for compensation. The population of the second type of Sn (site B) increases with the total Sn concentration, and this site is clearly electrically inactive. The site B MS parameters are similar to those of Sn3As2, SnAs, and β-Sn, thereby demonstrating that microprecipitates of these phases may often exist in heavily Sn-doped liquid-phase-epitaxial GaAs. Site B could also be due to clusters of Sn and/or Sn-As that are precursors to the formation of distinct precipitates of Sn3As, SnAs, or β-Sn. Annealing experiments yield a Sn-related acceptor that is very likely of the form SnGaVGa. In addition, precise MS parameters are reported for the intermetallic phases SnAs and Sn3As2.Type of Medium: Electronic ResourceURL: -
18Articles: DFG German National LicensesWilliamson, D. L. ; Kustas, F. M. ; Fobare, D. F. ; Misra, M. S.
[S.l.] : American Institute of Physics (AIP)
Published 1986Staff ViewISSN: 1089-7550Source: AIP Digital ArchiveTopics: PhysicsNotes: Information on phase transformations, solid solution alloying, compound formation, and residual stresses resulting from Ti implantation of AISI 52100 steel is obtained using 57Fe Mössbauer spectroscopy. Results show that Ti implantation reduced the near-surface (0.1 μm) retained austenite content by about 70% or more and evidence is found for an implantation-induced strain field which extends much deeper than the Ti-implanted zone. Changes in the near-surface martensite Mössbauer resonance are attributed to Ti on substitutional sites. Neither of the intermetallic compounds Fe2Ti or FeTi, nor the amorphous Fe–Ti or Fe–Ti–C phases are unambiguously detected. However some features of the data are not explained by Ti and/or C solid solution alloy analysis and this leads to suggestions for a(approximately-less-than)10-nm-thick amorphous phase layer and surface oxides/carbides. The microstructural modifications are correlated with tribological properties measured on the same specimens. Improvements are attributed to the retained austenite reduction, residual compressive stresses in the near-surface layer, and the surface compounds.Type of Medium: Electronic ResourceURL: -
19Articles: DFG German National LicensesWilliamson, D. L. ; Gibart, P. ; El Jani, B. ; N'Guessan, K.
[S.l.] : American Institute of Physics (AIP)
Published 1987Staff ViewISSN: 1089-7550Source: AIP Digital ArchiveTopics: PhysicsNotes: GaAs epitaxial layers, doped with 119Sn-enriched tin, have been grown by metalorganic vapor-phase epitaxy (MOVPE). 119Sn Mössbauer spectroscopy and Hall measurements have been used to characterize the layers. Three tin species are observed in the as-grown material. One of these is identified as the SnGa shallow donor site and another is associated with electrically inactive Sn sites that may be SnGaSnAs pairs or Sn3As2-like clusters or microprecipitates. The free carrier concentrations (Nd−Na) obtained from the Hall data agree quantitatively with the concentrations of SnGa sites from the Mössbauer data for samples prepared with MOVPE Sn/Ga ratios up to 0.02 and Nd−Na 〈6×1018 cm−3, thereby showing no evidence for compensation up to this doping level. Annealing under arsine creates an acceptor species which is identified as SnGaVGa. High-energy electron irradiation may also produce this compensating acceptor species.Type of Medium: Electronic ResourceURL: -
20Articles: DFG German National LicensesGuha, S. ; Yang, J. ; Jones, Scott J. ; Chen, Yan ; Williamson, D. L.
Woodbury, NY : American Institute of Physics (AIP)
Published 1992Staff ViewISSN: 1077-3118Source: AIP Digital ArchiveTopics: PhysicsNotes: Using a combination of infrared absorption and small-angle x-ray scattering on hydrogenated amorphous silicon alloy films and efficiency measurements of solar cells with intrinsic layers prepared under nominally identical conditions to those for the deposition of the films, we observe a correlation between microstructure in the films and solar cell performance. With increasing microvoid density, both the initial and light-degraded performance of solar cells are found to deteriorate.Type of Medium: Electronic ResourceURL: