1
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Pillonel V, Juskevicius D, Ng CKY, Bodmer A, Zettl A, Jucker D, Dirnhofer S, Tzankov A. High-throughput sequencing of nodal marginal zone lymphomas identifies recurrent BRAF mutations. Leukemia 2018; 32:2412-2426. [PMID: 29556019 PMCID: PMC6224405 DOI: 10.1038/s41375-018-0082-4] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2017] [Revised: 01/15/2018] [Accepted: 02/05/2018] [Indexed: 12/23/2022]
Abstract
Nodal marginal zone lymphoma (NMZL) is a rare small B-cell lymphoma lacking disease-defining phenotype and precise diagnostic markers. To better understand the mutational landscape of NMZL, particularly in comparison to other nodal small B-cell lymphomas, we performed whole-exome sequencing, targeted high-throughput sequencing, and array-comparative genomic hybridization on a retrospective series. Our study identified for the first time recurrent, diagnostically useful, and potentially therapeutically relevant BRAF mutations in NMZL. Sets of somatic mutations that could help to discriminate NMZL from other closely related small B-cell lymphomas were uncovered and tested on unclassifiable small B-cell lymphoma cases, in which clinical, morphological, and phenotypical features were equivocal. Application of targeted gene panel sequencing gave at many occasions valuable clues for more specific classification.
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Affiliation(s)
- V Pillonel
- Institute of Pathology and Medical Genetics, University Hospital Basel, University of Basel, Basel, Switzerland
| | - D Juskevicius
- Institute of Pathology and Medical Genetics, University Hospital Basel, University of Basel, Basel, Switzerland
| | - C K Y Ng
- Institute of Pathology and Medical Genetics, University Hospital Basel, University of Basel, Basel, Switzerland.,Department of Biomedicine, University Hospital Basel, Basel, Switzerland
| | - A Bodmer
- Institute of Pathology, Cantonal Hospital Baselland, Liestal, Switzerland
| | - A Zettl
- Pathology, Viollier AG, Allschwil, Switzerland
| | - D Jucker
- Institute of Pathology and Medical Genetics, University Hospital Basel, University of Basel, Basel, Switzerland
| | - S Dirnhofer
- Institute of Pathology and Medical Genetics, University Hospital Basel, University of Basel, Basel, Switzerland
| | - A Tzankov
- Institute of Pathology and Medical Genetics, University Hospital Basel, University of Basel, Basel, Switzerland.
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2
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Gerding H, Zettl A, Timmermann M. Bothersome Cutaneous Lesion for more than 30 Years: Dilated Pore of Winer. Klin Monbl Augenheilkd 2017; 234:595-596. [DOI: 10.1055/s-0043-100562] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Affiliation(s)
- H. Gerding
- Augenzentrum Pallas Kliniken, Olten, Switzerland (Director: Prof. Dr. med. Heinrich Gerding, F. E. B. O.)
| | - A. Zettl
- Institut für Pathologie Viollier, Allschwil, Switzerland (Head: Priv.-Doz. Dr. med. Andreas Zettl)
| | - M. Timmermann
- Augenzentrum Pallas Kliniken, Olten, Switzerland (Director: Prof. Dr. med. Heinrich Gerding, F. E. B. O.)
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3
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Fei Z, Foley JJ, Gannett W, Liu MK, Dai S, Ni GX, Zettl A, Fogler MM, Wiederrecht GP, Gray SK, Basov DN. Ultraconfined Plasmonic Hotspots Inside Graphene Nanobubbles. Nano Lett 2016; 16:7842-7848. [PMID: 27960518 DOI: 10.1021/acs.nanolett.6b04076] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
We report on a nanoinfrared (IR) imaging study of ultraconfined plasmonic hotspots inside graphene nanobubbles formed in graphene/hexagonal boron nitride (hBN) heterostructures. The volume of these plasmonic hotspots is more than one-million-times smaller than what could be achieved by free-space IR photons, and their real-space distributions are controlled by the sizes and shapes of the nanobubbles. Theoretical analysis indicates that the observed plasmonic hotspots are formed due to a significant increase of the local plasmon wavelength in the nanobubble regions. Such an increase is attributed to the high sensitivity of graphene plasmons to its dielectric environment. Our work presents a novel scheme for plasmonic hotspot formation and sheds light on future applications of graphene nanobubbles for plasmon-enhanced IR spectroscopy.
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Affiliation(s)
- Z Fei
- Department of Physics, University of California, San Diego , La Jolla, California 92093, United States
- Center for Nanoscale Materials, Argonne National Laboratory , Argonne, Illinois 60439, United States
- Department of Physics and Astronomy, Iowa State University , Ames, Iowa 50011, United States
| | - J J Foley
- Center for Nanoscale Materials, Argonne National Laboratory , Argonne, Illinois 60439, United States
- Department of Chemistry, William Paterson University , Wayne, New Jersey 07470, United States
| | - W Gannett
- Department of Physics, University of California at Berkeley , Berkeley, California 94720, United States
- Materials Sciences Division, Lawrence Berkeley National Laboratory , Berkeley, California 94720, United States
| | - M K Liu
- Department of Physics, University of California, San Diego , La Jolla, California 92093, United States
- Department of Physics and Astronomy, Stony Brook University , Stony Brook, New York 11794, United States
| | - S Dai
- Department of Physics, University of California, San Diego , La Jolla, California 92093, United States
| | - G X Ni
- Department of Physics, University of California, San Diego , La Jolla, California 92093, United States
| | - A Zettl
- Department of Physics, University of California at Berkeley , Berkeley, California 94720, United States
- Materials Sciences Division, Lawrence Berkeley National Laboratory , Berkeley, California 94720, United States
| | - M M Fogler
- Department of Physics, University of California, San Diego , La Jolla, California 92093, United States
| | - G P Wiederrecht
- Center for Nanoscale Materials, Argonne National Laboratory , Argonne, Illinois 60439, United States
| | - S K Gray
- Center for Nanoscale Materials, Argonne National Laboratory , Argonne, Illinois 60439, United States
| | - D N Basov
- Department of Physics, University of California, San Diego , La Jolla, California 92093, United States
- Department of Physics, Columbia University , New York, New York 10027, United States
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4
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Weixler B, Warschkow R, Güller U, Zettl A, von Holzen U, Schmied BM, Zuber M. Isolated tumor cells in stage I & II colon cancer patients are associated with significantly worse disease-free and overall survival. BMC Cancer 2016; 16:106. [PMID: 26879046 PMCID: PMC4754888 DOI: 10.1186/s12885-016-2130-7] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2014] [Accepted: 02/04/2016] [Indexed: 12/18/2022] Open
Abstract
Background Lymph node (LN) involvement represents the strongest prognostic factor in colon cancer patients. The objective of this prospective study was to assess the prognostic impact of isolated tumor cells (ITC, defined as cell deposits ≤ 0.2 mm) in loco-regional LN of stage I & II colon cancer patients. Methods Seventy-four stage I & II colon cancer patients were prospectively enrolled in the present study. LN at high risk of harboring ITC were identified via an in vivo sentinel lymph node procedure and analyzed with multilevel sectioning, conventional H&E and immunohistochemical CK-19 staining. The impact of ITC on survival was assessed using Cox regression analyses. Results Median follow-up was 4.6 years. ITC were detected in locoregional lymph nodes of 23 patients (31.1 %). The presence of ITC was associated with a significantly worse disease-free survival (hazard ratio = 4.73, p = 0.005). Similarly, ITC were associated with significantly worse overall survival (hazard ratio = 3.50, p = 0.043). Conclusions This study provides compelling evidence that ITC in stage I & II colon cancer patients are associated with significantly worse disease-free and overall survival. Based on these data, the presence of ITC should be classified as a high risk factor in stage I & II colon cancer patients who might benefit from adjuvant chemotherapy.
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Affiliation(s)
- B Weixler
- Department of Surgery, Kantonsspital Olten, Baslerstrasse 150, CH - 4600, Olten, Switzerland.,Department of Surgery, University Hospital Basel, Basel, Switzerland
| | - R Warschkow
- Department of Surgery, Kantonsspital St. Gallen, St. Gallen, Switzerland.,Institute of Medical Biometry and Informatics, University of Heidelberg, Heidelberg, Germany
| | - U Güller
- Department of Oncology/Hematology, Kantonsspital St. Gallen, St. Gallen, Switzerland.,University Clinic for Visceral Surgery and Medicine, Inselspital Berne, University of Berne, Berne, Switzerland
| | - A Zettl
- Viollier AG, Histopathology/Cytology, Basel, Switzerland
| | - U von Holzen
- Department of Surgery, University Hospital Basel, Basel, Switzerland
| | - B M Schmied
- Department of Surgery, Kantonsspital St. Gallen, St. Gallen, Switzerland
| | - M Zuber
- Department of Surgery, Kantonsspital Olten, Baslerstrasse 150, CH - 4600, Olten, Switzerland.
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5
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Park J, Elmlund H, Ercius P, Yuk JM, Limmer DT, Chen Q, Kim K, Han SH, Weitz DA, Zettl A, Alivisatos AP. 3D structure of individual nanocrystals in solution by electron microscopy. Science 2015; 349:290-5. [DOI: 10.1126/science.aab1343] [Citation(s) in RCA: 198] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2015] [Accepted: 06/04/2015] [Indexed: 01/19/2023]
Abstract
Knowledge about the synthesis, growth mechanisms, and physical properties of colloidal nanoparticles has been limited by technical impediments. We introduce a method for determining three-dimensional (3D) structures of individual nanoparticles in solution. We combine a graphene liquid cell, high-resolution transmission electron microscopy, a direct electron detector, and an algorithm for single-particle 3D reconstruction originally developed for analysis of biological molecules. This method yielded two 3D structures of individual platinum nanocrystals at near-atomic resolution. Because our method derives the 3D structure from images of individual nanoparticles rotating freely in solution, it enables the analysis of heterogeneous populations of potentially unordered nanoparticles that are synthesized in solution, thereby providing a means to understand the structure and stability of defects at the nanoscale.
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Affiliation(s)
- Jungwon Park
- Department of Chemistry, University of California, Berkeley, CA 94720, USA
- Department of Applied Physics, Harvard University, Cambridge, MA 02138, USA
- School of Engineering and Applied Sciences, Harvard University, Cambridge, MA 02138, USA
| | - Hans Elmlund
- Department of Biochemistry and Molecular Biology, School of Biomedical Sciences, Monash University, Clayton, VIC 3800, Australia
- ARC Centre of Excellence for Advanced Molecular Imaging, Clayton, VIC 3800, Australia
| | - Peter Ercius
- Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Jong Min Yuk
- Department of Physics, University of California, Berkeley, CA 94720, USA
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
- Kavli Energy NanoScience Institute, Berkeley, CA 94720, USA
| | - David T. Limmer
- Princeton Center for Theoretical Science, Princeton University, Princeton, NJ 08540, USA
| | - Qian Chen
- Department of Chemistry, University of California, Berkeley, CA 94720, USA
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
- Miller Institute for Basic Research in Science, University of California, Berkeley, CA 93720, USA
| | - Kwanpyo Kim
- Department of Physics, Ulsan National Institute of Science and Technology, Ulsan 689-798, South Korea
| | - Sang Hoon Han
- Amore-Pacific Co. R&D Center, Yongin 446-829, South Korea
| | - David A. Weitz
- Department of Applied Physics, Harvard University, Cambridge, MA 02138, USA
- School of Engineering and Applied Sciences, Harvard University, Cambridge, MA 02138, USA
| | - A. Zettl
- Department of Physics, University of California, Berkeley, CA 94720, USA
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
- Kavli Energy NanoScience Institute, Berkeley, CA 94720, USA
| | - A. Paul Alivisatos
- Department of Chemistry, University of California, Berkeley, CA 94720, USA
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
- Kavli Energy NanoScience Institute, Berkeley, CA 94720, USA
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6
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Huang X, Zhao Z, Cao L, Chen Y, Zhu E, Lin Z, Li M, Yan A, Zettl A, Wang YM, Duan X, Mueller T, Huang Y. High-performance transition metal-doped Pt3Ni octahedra for oxygen reduction reaction. Science 2015; 348:1230-4. [DOI: 10.1126/science.aaa8765] [Citation(s) in RCA: 1345] [Impact Index Per Article: 149.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2015] [Accepted: 05/04/2015] [Indexed: 11/02/2022]
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7
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Shi SF, Zeng B, Han HL, Hong X, Tsai HZ, Jung HS, Zettl A, Crommie MF, Wang F. Optimizing broadband terahertz modulation with hybrid graphene/metasurface structures. Nano Lett 2015; 15:372-377. [PMID: 25483819 DOI: 10.1021/nl503670d] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
We demonstrate efficient terahertz (THz) modulation by coupling graphene strongly with a broadband THz metasurface device. This THz metasurface, made of periodic gold slit arrays, shows near unity broadband transmission, which arises from coherent radiation of the enhanced local-field in the slits. Utilizing graphene as an active load with tunable conductivity, we can significantly modify the local-field enhancement and strongly modulate the THz wave transmission. This hybrid device also provides a new platform for future nonlinear THz spectroscopy study of graphene.
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Affiliation(s)
- S-F Shi
- Department of Physics, University of California at Berkeley , Berkeley, California 94720, United States
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8
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Ju L, Velasco J, Huang E, Kahn S, Nosiglia C, Tsai HZ, Yang W, Taniguchi T, Watanabe K, Zhang Y, Zhang G, Crommie M, Zettl A, Wang F. Photoinduced doping in heterostructures of graphene and boron nitride. Nat Nanotechnol 2014; 9:348-52. [PMID: 24727687 DOI: 10.1038/nnano.2014.60] [Citation(s) in RCA: 133] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2013] [Accepted: 02/21/2014] [Indexed: 05/15/2023]
Abstract
The design of stacks of layered materials in which adjacent layers interact by van der Waals forces has enabled the combination of various two-dimensional crystals with different electrical, optical and mechanical properties as well as the emergence of novel physical phenomena and device functionality. Here, we report photoinduced doping in van der Waals heterostructures consisting of graphene and boron nitride layers. It enables flexible and repeatable writing and erasing of charge doping in graphene with visible light. We demonstrate that this photoinduced doping maintains the high carrier mobility of the graphene/boron nitride heterostructure, thus resembling the modulation doping technique used in semiconductor heterojunctions, and can be used to generate spatially varying doping profiles such as p-n junctions. We show that this photoinduced doping arises from microscopically coupled optical and electrical responses of graphene/boron nitride heterostructures, including optical excitation of defect transitions in boron nitride, electrical transport in graphene, and charge transfer between boron nitride and graphene.
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Affiliation(s)
- L Ju
- 1] Department of Physics, University of California, Berkeley, California 94720, USA [2]
| | - J Velasco
- 1] Department of Physics, University of California, Berkeley, California 94720, USA [2]
| | - E Huang
- Department of Physics, University of California, Berkeley, California 94720, USA
| | - S Kahn
- Department of Physics, University of California, Berkeley, California 94720, USA
| | - C Nosiglia
- Department of Physics, University of California, Berkeley, California 94720, USA
| | - Hsin-Zon Tsai
- Department of Physics, University of California, Berkeley, California 94720, USA
| | - W Yang
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - T Taniguchi
- National Institute for Materials Science, 1-1 Namiki, Tsukuba, 305-0044, Japan
| | - K Watanabe
- National Institute for Materials Science, 1-1 Namiki, Tsukuba, 305-0044, Japan
| | - Y Zhang
- State Key Laboratory of Surface Physics and Department of Physics, Fudan University, Shanghai 200433, China
| | - G Zhang
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - M Crommie
- 1] Department of Physics, University of California, Berkeley, California 94720, USA [2] Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA [3] Kavli Energy NanoSciences Institute at the University of California, Berkeley and the Lawrence Berkeley National Laboratory, Berkeley, California, 94720, USA
| | - A Zettl
- 1] Department of Physics, University of California, Berkeley, California 94720, USA [2] Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA [3] Kavli Energy NanoSciences Institute at the University of California, Berkeley and the Lawrence Berkeley National Laboratory, Berkeley, California, 94720, USA
| | - F Wang
- 1] Department of Physics, University of California, Berkeley, California 94720, USA [2] Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA [3] Kavli Energy NanoSciences Institute at the University of California, Berkeley and the Lawrence Berkeley National Laboratory, Berkeley, California, 94720, USA
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9
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Dai S, Fei Z, Ma Q, Rodin AS, Wagner M, McLeod AS, Liu MK, Gannett W, Regan W, Watanabe K, Taniguchi T, Thiemens M, Dominguez G, Castro Neto AH, Zettl A, Keilmann F, Jarillo-Herrero P, Fogler MM, Basov DN. Tunable phonon polaritons in atomically thin van der Waals crystals of boron nitride. Science 2014; 343:1125-9. [PMID: 24604197 DOI: 10.1126/science.1246833] [Citation(s) in RCA: 434] [Impact Index Per Article: 43.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
van der Waals heterostructures assembled from atomically thin crystalline layers of diverse two-dimensional solids are emerging as a new paradigm in the physics of materials. We used infrared nanoimaging to study the properties of surface phonon polaritons in a representative van der Waals crystal, hexagonal boron nitride. We launched, detected, and imaged the polaritonic waves in real space and altered their wavelength by varying the number of crystal layers in our specimens. The measured dispersion of polaritonic waves was shown to be governed by the crystal thickness according to a scaling law that persists down to a few atomic layers. Our results are likely to hold true in other polar van der Waals crystals and may lead to new functionalities.
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Affiliation(s)
- S Dai
- Department of Physics, University of California, San Diego (UCSD), La Jolla, CA 92093, USA
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10
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Shi SF, Tang TT, Zeng B, Ju L, Zhou Q, Zettl A, Wang F. Controlling graphene ultrafast hot carrier response from metal-like to semiconductor-like by electrostatic gating. Nano Lett 2014; 14:1578-82. [PMID: 24564302 DOI: 10.1021/nl404826r] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
We investigate the ultrafast terahertz response of electrostatically gated graphene upon optical excitation. We observe that the photoinduced terahertz absorption increases in charge neutral graphene but decreases in highly doped graphene. We show that this transition from semiconductor-like to metal-like response is unique for zero bandgap materials such as graphene. In charge neutral graphene photoexcited hot carriers effectively increase electron and hole densities and increase the conductivity. In highly doped graphene, however, photoexcitation does not change net conducting carrier concentration. Instead, it mainly increases electron scattering rate and reduce the conductivity.
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Affiliation(s)
- S-F Shi
- Department of Physics, University of California at Berkeley , Berkeley, California 94720, United States
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11
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Rasool HI, Ophus C, Klug WS, Zettl A, Gimzewski JK. Measurement of the intrinsic strength of crystalline and polycrystalline graphene. Nat Commun 2013. [DOI: 10.1038/ncomms3811] [Citation(s) in RCA: 217] [Impact Index Per Article: 19.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
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12
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Fei Z, Rodin AS, Gannett W, Dai S, Regan W, Wagner M, Liu MK, McLeod AS, Dominguez G, Thiemens M, Castro Neto AH, Keilmann F, Zettl A, Hillenbrand R, Fogler MM, Basov DN. Electronic and plasmonic phenomena at graphene grain boundaries. Nat Nanotechnol 2013; 8:821-5. [PMID: 24122082 DOI: 10.1038/nnano.2013.197] [Citation(s) in RCA: 116] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2013] [Accepted: 09/06/2013] [Indexed: 05/11/2023]
Abstract
Graphene, a two-dimensional honeycomb lattice of carbon atoms of great interest in (opto)electronics and plasmonics, can be obtained by means of diverse fabrication techniques, among which chemical vapour deposition (CVD) is one of the most promising for technological applications. The electronic and mechanical properties of CVD-grown graphene depend in large part on the characteristics of the grain boundaries. However, the physical properties of these grain boundaries remain challenging to characterize directly and conveniently. Here we show that it is possible to visualize and investigate the grain boundaries in CVD-grown graphene using an infrared nano-imaging technique. We harness surface plasmons that are reflected and scattered by the graphene grain boundaries, thus causing plasmon interference. By recording and analysing the interference patterns, we can map grain boundaries for a large-area CVD graphene film and probe the electronic properties of individual grain boundaries. Quantitative analysis reveals that grain boundaries form electronic barriers that obstruct both electrical transport and plasmon propagation. The effective width of these barriers (∼10-20 nm) depends on the electronic screening and is on the order of the Fermi wavelength of graphene. These results uncover a microscopic mechanism that is responsible for the low electron mobility observed in CVD-grown graphene, and suggest the possibility of using electronic barriers to realize tunable plasmon reflectors and phase retarders in future graphene-based plasmonic circuits.
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Affiliation(s)
- Z Fei
- Department of Physics, University of California, San Diego, La Jolla, California 92093, USA
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13
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Coh S, Gannett W, Zettl A, Cohen ML, Louie SG. Surface atom motion to move iron nanocrystals through constrictions in carbon nanotubes under the action of an electric current. Phys Rev Lett 2013; 110:185901. [PMID: 23683222 DOI: 10.1103/physrevlett.110.185901] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2013] [Indexed: 06/02/2023]
Abstract
Under the application of electrical currents, metal nanocrystals inside carbon nanotubes can be bodily transported. We examine experimentally and theoretically how an iron nanocrystal can pass through a constriction in the carbon nanotube with a smaller cross-sectional area than the nanocrystal itself. Remarkably, through in situ transmission electron imaging and diffraction, we find that, while passing through a constriction, the nanocrystal remains largely solid and crystalline and the carbon nanotube is unaffected. We account for this behavior by a pattern of iron atom motion and rearrangement on the surface of the nanocrystal. The nanocrystal motion can be described with a model whose parameters are nearly independent of the nanocrystal length, area, temperature, and electromigration force magnitude. We predict that metal nanocrystals can move through complex geometries and constrictions, with implications for both nanomechanics and tunable synthesis of metal nanoparticles.
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Affiliation(s)
- Sinisa Coh
- Department of Physics, University of California at Berkeley and Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA.
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14
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Abstract
The effect of charge-carrier screening on the transport properties of a neutral graphene sheet is studied by directly probing its electronic structure. We find that the Fermi velocity, Dirac point velocity, and overall distortion of the Dirac cone are renormalized due to the screening of the electron-electron interaction in an unusual way. We also observe an increase of the electron mean free path due to the screening of charged impurities. These observations help us to understand the basis for the transport properties of graphene, as well as the fundamental physics of these interesting electron-electron interactions at the Dirac point crossing.
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Affiliation(s)
- David A Siegel
- Department of Physics, University of California, Berkeley, California 94720, USA and Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - William Regan
- Department of Physics, University of California, Berkeley, California 94720, USA and Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - Alexei V Fedorov
- Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - A Zettl
- Department of Physics, University of California, Berkeley, California 94720, USA and Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - Alessandra Lanzara
- Department of Physics, University of California, Berkeley, California 94720, USA and Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
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15
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Wang Y, Wong D, Shytov AV, Brar VW, Choi S, Wu Q, Tsai HZ, Regan W, Zettl A, Kawakami RK, Louie SG, Levitov LS, Crommie MF. Observing Atomic Collapse Resonances in Artificial Nuclei on Graphene. Science 2013; 340:734-7. [DOI: 10.1126/science.1234320] [Citation(s) in RCA: 190] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
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16
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Alem N, Ramasse QM, Seabourne CR, Yazyev OV, Erickson K, Sarahan MC, Kisielowski C, Scott AJ, Louie SG, Zettl A. Subangstrom edge relaxations probed by electron microscopy in hexagonal boron nitride. Phys Rev Lett 2012; 109:205502. [PMID: 23215505 DOI: 10.1103/physrevlett.109.205502] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2012] [Indexed: 06/01/2023]
Abstract
Theoretical research on the two-dimensional crystal structure of hexagonal boron nitride (h-BN) has suggested that the physical properties of h-BN can be tailored for a wealth of applications by controlling the atomic structure of the membrane edges. Unexplored for h-BN, however, is the possibility that small additional edge-atom distortions could have electronic structure implications critically important to nanoengineering efforts. Here we demonstrate, using a combination of analytical scanning transmission electron microscopy and density functional theory, that covalent interlayer bonds form spontaneously at the edges of a h-BN bilayer, resulting in subangstrom distortions of the edge atomic structure. Orbital maps calculated in 3D around the closed edge reveal that the out-of-plane bonds retain a strong π(*) character. We show that this closed edge reconstruction, strikingly different from the equivalent case for graphene, helps the material recover its bulklike insulating behavior and thus largely negates the predicted metallic character of open edges.
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Affiliation(s)
- Nasim Alem
- Department of Physics, University of California Berkeley, Berkeley, California 94720, USA
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17
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Kim K, Coh S, Tan LZ, Regan W, Yuk JM, Chatterjee E, Crommie MF, Cohen ML, Louie SG, Zettl A. Raman spectroscopy study of rotated double-layer graphene: misorientation-angle dependence of electronic structure. Phys Rev Lett 2012; 108:246103. [PMID: 23004295 DOI: 10.1103/physrevlett.108.246103] [Citation(s) in RCA: 100] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2012] [Revised: 04/13/2012] [Indexed: 06/01/2023]
Abstract
We present a systematic Raman study of unconventionally stacked double-layer graphene, and find that the spectrum strongly depends on the relative rotation angle between layers. Rotation-dependent trends in the position, width and intensity of graphene 2D and G peaks are experimentally established and accounted for theoretically. Our theoretical analysis reveals that changes in electronic band structure due to the interlayer interaction, such as rotational-angle dependent Van Hove singularities, are responsible for the observed spectral features. Our combined experimental and theoretical study provides a deeper understanding of the electronic band structure of rotated double-layer graphene, and leads to a practical way to identify and analyze rotation angles of misoriented double-layer graphene.
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Affiliation(s)
- Kwanpyo Kim
- Department of Physics, University of California at Berkeley, Berkeley, California 94720, USA
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18
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Yuk JM, Park J, Ercius P, Kim K, Hellebusch DJ, Crommie MF, Lee JY, Zettl A, Alivisatos AP. High-resolution EM of colloidal nanocrystal growth using graphene liquid cells. Science 2012; 336:61-4. [PMID: 22491849 DOI: 10.1126/science.1217654] [Citation(s) in RCA: 590] [Impact Index Per Article: 49.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
We introduce a new type of liquid cell for in situ transmission electron microscopy (TEM) based on entrapment of a liquid film between layers of graphene. The graphene liquid cell facilitates atomic-level resolution imaging while sustaining the most realistic liquid conditions achievable under electron-beam radiation. We employ this cell to explore the mechanism of colloidal platinum nanocrystal growth. Direct atomic-resolution imaging allows us to visualize critical steps in the process, including site-selective coalescence, structural reshaping after coalescence, and surface faceting.
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Affiliation(s)
- Jong Min Yuk
- Department of Physics, University of California at Berkeley, Berkeley, CA 94720, USA
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19
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Abstract
The understanding of crack formation due to applied stress is key to predicting the ultimate mechanical behavior of many solids. Here we present experimental and theoretical studies on cracks or tears in suspended monolayer graphene membranes. Using transmission electron microscopy, we investigate the crystallographic orientations of tears. Edges from mechanically induced ripping exhibit straight lines and are predominantly aligned in the armchair or zigzag directions of the graphene lattice. Electron-beam induced propagation of tears is also observed. Theoretical simulations account for the observed preferred tear directions, attributing the observed effect to an unusual nonmonotonic dependence of graphene edge energy on edge orientation with respect to the lattice. Furthermore, we study the behavior of tears in the vicinity of graphene grain boundaries, where tears surprisingly do not follow but cross grain boundaries. Our study provides significant insights into breakdown mechanisms of graphene in the presence of defective structures such as cracks and grain boundaries.
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Affiliation(s)
- Kwanpyo Kim
- Department of Physics and Center of Integrated Nanomechanical Systems, University of California at Berkeley, Berkeley, California 94720, USA
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20
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Zuber M, Viehl C, Langer I, Zettl A, Guller U. 318 INVITED Better Survival due to Improved Staging in Colon Cancer, the Sentinel Node Reappraised. Eur J Cancer 2011. [DOI: 10.1016/s0959-8049(11)70533-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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21
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22
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Alem N, Yazyev OV, Kisielowski C, Denes P, Dahmen U, Hartel P, Haider M, Bischoff M, Jiang B, Louie SG, Zettl A. Probing the out-of-plane distortion of single point defects in atomically thin hexagonal boron nitride at the picometer scale. Phys Rev Lett 2011; 106:126102. [PMID: 21517331 DOI: 10.1103/physrevlett.106.126102] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2010] [Indexed: 05/30/2023]
Abstract
Crystalline systems often lower their energy by atom displacements from regular high-symmetry lattice sites. We demonstrate that such symmetry lowering distortions can be visualized by ultrahigh resolution transmission electron microscopy even at single point defects. Experimental investigation of structural distortions at the monovacancy defects in suspended bilayers of hexagonal boron nitride (h-BN) accompanied by first-principles calculations reveals a characteristic charge-induced pm symmetry configuration of boron vacancies. This symmetry breaking is caused by interlayer bond reconstruction across the bilayer h-BN at the negatively charged boron vacancy defects and results in local membrane bending at the defect site. This study confirms that boron vacancies are dominantly present in the h-BN membrane.
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Affiliation(s)
- Nasim Alem
- Department of Physics, University of California, Berkeley, California 94720, USA
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23
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Abstract
We report direct mapping of the grains and grain boundaries (GBs) of large-area monolayer polycrystalline graphene sheets, at large (several micrometer) and single-atom length scales. Global grain and GB mapping is performed using electron diffraction in scanning transmission electron microscopy (STEM) or using dark-field imaging in conventional TEM. Additionally, we employ aberration-corrected TEM to extract direct images of the local atomic arrangements of graphene GBs, which reveal the alternating pentagon-heptagon structure along high-angle GBs. Our findings provide a readily adaptable tool for graphene GB studies.
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Affiliation(s)
- Kwanpyo Kim
- Department of Physics and Center of Integrated Nanomechanical Systems, University of California at Berkeley, Berkeley, California 94720, United States
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24
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Alemán B, Regan W, Aloni S, Altoe V, Alem N, Girit C, Geng B, Maserati L, Crommie M, Wang F, Zettl A. Transfer-free batch fabrication of large-area suspended graphene membranes. ACS Nano 2010; 4:4762-8. [PMID: 20604526 DOI: 10.1021/nn100459u] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
We demonstrate a process for batch production of large-area (100-3000 microm(2)) patterned free-standing graphene membranes on Cu scaffolds using chemical vapor deposition (CVD)-grown graphene. This technique avoids the use of silicon and transfers of graphene. As one application of this technique, we fabricate transmission electron microscopy (TEM) sample supports. TEM characterization of the graphene membranes reveals relatively clean, highly TEM-transparent, single-layer graphene regions ( approximately 50% by area) and, despite the polycrystalline nature of CVD graphene, membrane yields as high as 75-100%. This high yield verifies that the intrinsic strength and integrity of CVD-grown graphene films is sufficient for sub-100 microm width membrane applications. Elemental analysis (electron energy loss spectroscopy (EELS) and X-ray energy-dispersive spectroscopy (EDS)) of the graphene membranes reveals some nanoscaled contamination left over from the etching process, and we suggest several ways to reduce this contamination and improve the quality of the graphene for electronic device applications. This large-scale production of suspended graphene membranes facilitates access to the two-dimensional physics of graphene that are suppressed by substrate interactions and enables the widespread use of graphene-based sample supports for electron and optical microscopy.
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Affiliation(s)
- Benjamín Alemán
- Department of Physics, University of California at Berkeley, California 94720, USA
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25
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Levy N, Burke SA, Meaker KL, Panlasigui M, Zettl A, Guinea F, Neto AHC, Crommie MF. Strain-Induced Pseudo-Magnetic Fields Greater Than 300 Tesla in Graphene Nanobubbles. Science 2010; 329:544-7. [DOI: 10.1126/science.1191700] [Citation(s) in RCA: 1220] [Impact Index Per Article: 87.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
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26
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Pacilé D, Papagno M, Skála T, Matolín V, Sainsbury T, Ikuno T, Okawa D, Zettl A, Prince KC. Excitons at the B K edge of boron nitride nanotubes probed by x-ray absorption spectroscopy. J Phys Condens Matter 2010; 22:295301. [PMID: 21399297 DOI: 10.1088/0953-8984/22/29/295301] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
We have performed a near-edge x-ray absorption fine-structure (NEXAFS) investigation of multi-walled boron nitride nanotubes (BNNTs). We show that the one-dimensionality of BNNTs is clearly evident in the B K edge spectrum, while the N K edge spectrum is similar to that of layered hexagonal BN (h-BN). We observe a sharp feature at the σ* onset of the B K edge, which we ascribe to a core exciton state. We also report a comparison with spectra taken after an ammonia plasma treatment, showing that the B K edge becomes indistinguishable from that of h-BN, due to the breaking of the tubular order and the formation of small h-BN clusters.
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Affiliation(s)
- D Pacilé
- Istituto Nazionale di Fisica Nucleare (INFN) and Dipartimento di Fisica Università della Calabria, Cosenza, Italy
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27
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Yuk JM, Kim K, Lee Z, Watanabe M, Zettl A, Kim TW, No YS, Choi WK, Lee JY. Direct fabrication of zero- and one-dimensional metal nanocrystals by thermally assisted electromigration. ACS Nano 2010; 4:2999-3004. [PMID: 20465220 DOI: 10.1021/nn901674p] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Zero- and one-dimensional metal nanocrystals were successfully fabricated with accurate control in size, shape, and position on semiconductor surfaces by using a novel in situ fabrication method of the nanocrystal with a biasing tungsten tip in transmission electron microscopy. The dominant mechanism of nanocrystal formation was identified mainly as local Joule heating-assisted electromigration through the direct observation of formation and growth processes of the nanocrystal. This method was applied to extracting metal atoms with an exceedingly faster growth rate ( approximately 10(5) atoms/s) from a metal-oxide thin film to form a metal nanocrystal with any desired size and position. By real-time observation of the microstructure and concurrent electrical measurements, it was found that the nanostructure formation can be completely controlled into various shapes such as zero-dimensional nanodots and one-dimensional nanowires/nanorods.
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Affiliation(s)
- Jong Min Yuk
- Department of Materials Science and Engineering, KAIST, Daejeon 305-701, Korea
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28
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Abstract
We describe a clean method of graphene nanoribbon (GNR) extraction from multiwall carbon nanotubes (MWNTs), performed in a high vacuum, nonchemical environment. Electrical current and nanomanipulation are used to unwrap a portion of the MWNT and thus produce a GNR of desired width and length. The unwrapping method allows GNRs to be concurrently characterized structurally via high-resolution transmission electron microscopy (TEM) and evaluated for electrical transport, including situations for which the GNR is severely mechanically flexed. High quality GNRs have exceptional current-carrying capacity, comparable to the exfoliated graphene.
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Affiliation(s)
- Kwanpyo Kim
- Department of Physics, University of California at Berkeley, Center of Integrated Nanomechanical Systems, University of California at Berkeley, Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
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29
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Kessler BM, Girit CO, Zettl A, Bouchiat V. Tunable superconducting phase transition in metal-decorated graphene sheets. Phys Rev Lett 2010; 104:047001. [PMID: 20366731 DOI: 10.1103/physrevlett.104.047001] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/08/2009] [Indexed: 05/29/2023]
Abstract
We have produced graphene sheets decorated with a nonpercolating network of nanoscale tin clusters. These metal clusters both efficiently dope the graphene substrate and induce long-range superconducting correlations. We find that despite structural inhomogeneity on mesoscopic length scales (10-100 nm), this material behaves electronically as a homogenous dirty superconductor with a field-effect tuned Berezinskii-Kosterlitz-Thouless transition. Our facile self-assembly method establishes graphene as an ideal tunable substrate for studying induced two-dimensional electronic systems at fixed disorder and our technique can readily be extended to other order parameters such as magnetism.
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Affiliation(s)
- B M Kessler
- Department of Physics, University of California at Berkeley, Berkeley, California 94720, USA
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30
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Kim Y, Abou-Hamad E, Rubio A, Wågberg T, Talyzin AV, Boesch D, Aloni S, Zettl A, Luzzi DE, Goze-Bac C. Communications: Nanomagnetic shielding: High-resolution NMR in carbon allotropes. J Chem Phys 2010; 132:021102. [DOI: 10.1063/1.3284740] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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31
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Abou-Hamad E, Kim Y, Wågberg T, Boesch D, Aloni S, Zettl A, Rubio A, Luzzi DE, Goze-Bac C. Molecular dynamics and phase transition in one-dimensional crystal of C(60) encapsulated inside single wall carbon nanotubes. ACS Nano 2009; 3:3878-3883. [PMID: 19911833 DOI: 10.1021/nn901128t] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Affiliation(s)
- E Abou-Hamad
- Laboratoire Colloides, Verres et Nanomateriaux, CNRS Universite Montpellier 2, France
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32
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Abstract
We demonstrate tuning of nanoelectromechanical resonators via mass migration. Indium nanoparticles can be reversibly migrated to different locations along cantilevered multiwalled carbon nanotube resonators using electrical currents as the control parameter. Nonvolatile mass redistributions result in stable resonant frequency shifts as large as 20%. The tuning method is robust and can be utilized for nanoelectromechanical resonators operating at frequencies from audio to microwave.
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Affiliation(s)
- Kwanpyo Kim
- Department of Physics and Center of Integrated Nanomechanical Systems, University of California at Berkeley, Berkeley, California 94720, USA
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33
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Papagno M, Fraile Rodríguez A, Girit Ç, Meyer J, Zettl A, Pacilé D. Polarization-dependent C K near-edge X-ray absorption fine-structure of graphene. Chem Phys Lett 2009. [DOI: 10.1016/j.cplett.2009.05.054] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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34
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Abstract
The spleen is commonly affected by malignant lymphomas and the macroscopic findings of the spleen correlate with different lymphoma entities. However, most lymphomas are not primarily diagnosed in splenectomy specimens. Exceptions include splenic marginal zone lymphomas and hepatosplenic T-cell lymphomas that are typically diagnosed from histological findings. In addition, hairy-cell leukemia, LGL leukemia and T-cell prolymphocytic leukemia typically show characteristic patterns of infiltration in the spleen which may be diagnostically useful. The different infiltration patterns of these tumors are discussed here.
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Affiliation(s)
- A Marx
- Institut für Pathologie, Universitätsklinikum Mannheim, Mannheim
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35
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Abstract
We report on a simple electromechanical memory device in which an iron nanoparticle shuttle is controllably positioned within a hollow nanotube channel. The shuttle can be moved reversibly via an electrical write signal and can be positioned with nanoscale precision. The position of the shuttle can be read out directly via a blind resistance read measurement, allowing application as a nonvolatile memory element with potentially hundreds of memory states per device. The shuttle memory has application for archival storage, with information density as high as 10(12) bits/in(2), and thermodynamic stability in excess of one billion years.
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Affiliation(s)
- G E Begtrup
- Department of Physics, University of California, and Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
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36
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Girit CO, Meyer JC, Erni R, Rossell MD, Kisielowski C, Yang L, Park CH, Crommie MF, Cohen ML, Louie SG, Zettl A. Graphene at the edge: stability and dynamics. Science 2009; 323:1705-8. [PMID: 19325110 DOI: 10.1126/science.1166999] [Citation(s) in RCA: 505] [Impact Index Per Article: 33.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Although the physics of materials at surfaces and edges has been extensively studied, the movement of individual atoms at an isolated edge has not been directly observed in real time. With a transmission electron aberration-corrected microscope capable of simultaneous atomic spatial resolution and 1-second temporal resolution, we produced movies of the dynamics of carbon atoms at the edge of a hole in a suspended, single atomic layer of graphene. The rearrangement of bonds and beam-induced ejection of carbon atoms are recorded as the hole grows. We investigated the mechanism of edge reconstruction and demonstrated the stability of the "zigzag" edge configuration. This study of an ideal low-dimensional interface, a hole in graphene, exhibits the complex behavior of atoms at a boundary.
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Affiliation(s)
- Caglar O Girit
- Department of Physics, University of California at Berkeley, Berkeley, CA 94720, USA
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37
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Girit C, Bouchiat V, Naaman O, Zhang Y, Crommie MF, Zettl A, Siddiqi I. Tunable graphene dc superconducting quantum interference device. Nano Lett 2009; 9:198-199. [PMID: 19090696 DOI: 10.1021/nl802765x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Graphene exhibits unique electrical properties on account of its reduced dimensionality and "relativistic" band structure. When contacted with two superconducting electrodes, graphene can support Cooper pair transport, resulting in the well-known Josephson effect. We report here the fabrication and operation of a two junction dc superconducting quantum interference device (SQUID) formed by a single graphene sheet contacted with aluminum/palladium electrodes in the geometry of a loop. The supercurrent in this device can be modulated not only via an electrostatic gate but also by an applied magnetic fielda potentially powerful probe of electronic transport in graphene and an ultrasensitive platform for nanomagnetometry.
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Affiliation(s)
- Caglar Girit
- Department of Physics, University of California, Materials Sciences Division, Lawrence Berkeley National Laboratory, Quantum Nanoelectronics Laboratory, University of California, Berkeley, California 94720, USA
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38
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Meyer JC, Kisielowski C, Erni R, Rossell MD, Crommie MF, Zettl A. Direct imaging of lattice atoms and topological defects in graphene membranes. Nano Lett 2008; 8:3582-6. [PMID: 18563938 DOI: 10.1021/nl801386m] [Citation(s) in RCA: 421] [Impact Index Per Article: 26.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
We present a transmission electron microscopy investigation of graphene membranes, crystalline foils with a thickness of only 1 atom. By using aberration-correction in combination with a monochromator, 1-A resolution is achieved at an acceleration voltage of only 80 kV. The low voltage is crucial for the stability of these membranes. As a result, every individual carbon atom in the field of view is detected and resolved. We observe a highly crystalline lattice along with occasional point defects. The formation and annealing of Stone-Wales defects is observed in situ. Multiple five- and seven-membered rings appear exclusively in combinations that avoid dislocations and disclinations, in contrast to previous observations on highly curved (tube- or fullerene-like) graphene surfaces.
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Affiliation(s)
- Jannik C Meyer
- Materials Sciences Division, Lawrence Berkeley National Laboratory and Department of Physics, University of California at Berkeley, Berkeley, California 94720, USA
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39
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Wamsler MB, Girschick G, Zettl A, Dietl J, Rehn M. Dilatation der intraabdominalen Vena umbilicalis beim Feten: 2 Fallberichte. Geburtshilfe Frauenheilkd 2008. [DOI: 10.1055/s-0028-1088963] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
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40
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Jensen K, Kim K, Zettl A. An atomic-resolution nanomechanical mass sensor. Nat Nanotechnol 2008; 3:533-7. [PMID: 18772913 DOI: 10.1038/nnano.2008.200] [Citation(s) in RCA: 109] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/02/2008] [Accepted: 06/16/2008] [Indexed: 05/05/2023]
Abstract
Mechanical resonators are widely used as inertial balances to detect small quantities of adsorbed mass through shifts in oscillation frequency. Advances in lithography and materials synthesis have enabled the fabrication of nanoscale mechanical resonators, which have been operated as precision force, position and mass sensors. Here we demonstrate a room-temperature, carbon-nanotube-based nanomechanical resonator with atomic mass resolution. This device is essentially a mass spectrometer with a mass sensitivity of 1.3 x 10(-25) kg Hz(-1/2) or, equivalently, 0.40 gold atoms Hz(-1/2). Using this extreme mass sensitivity, we observe atomic mass shot noise, which is analogous to the electronic shot noise measured in many semiconductor experiments. Unlike traditional mass spectrometers, nanomechanical mass spectrometers do not require the potentially destructive ionization of the test sample, are more sensitive to large molecules, and could eventually be incorporated on a chip.
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41
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Chang CW, Okawa D, Garcia H, Majumdar A, Zettl A. Breakdown of Fourier's law in nanotube thermal conductors. Phys Rev Lett 2008; 101:075903. [PMID: 18764555 DOI: 10.1103/physrevlett.101.075903] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2008] [Revised: 07/09/2008] [Indexed: 05/26/2023]
Abstract
We present experimental evidence that the room temperature thermal conductivity (kappa) of individual multiwalled carbon and boron-nitride nanotubes does not obey Fourier's empirical law of thermal conduction. Because of isotopic disorder, kappa's of carbon nanotubes and boron-nitride nanotubes show different length dependence behavior. Moreover, for these systems we find that Fourier's law is violated even when the phonon mean free path is much shorter than the sample length.
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Affiliation(s)
- C W Chang
- Department of Physics, University of California at Berkeley, California 94720, USA.
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42
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Pacilé D, Papagno M, Rodríguez AF, Grioni M, Papagno L, Girit CO, Meyer JC, Begtrup GE, Zettl A. Near-edge x-ray absorption fine-structure investigation of graphene. Phys Rev Lett 2008; 101:066806. [PMID: 18764491 DOI: 10.1103/physrevlett.101.066806] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2008] [Indexed: 05/14/2023]
Abstract
We report the near-edge x-ray absorption fine-structure (NEXAFS) spectrum of a single layer of graphite (graphene) obtained by micromechanical cleavage of highly ordered pyrolytic graphite on a SiO2 substrate. We utilized a photoemission electron microscope to separately study single-, double-, and few-layers graphene samples. In single-layer graphene we observe a splitting of the pi resonance and a clear signature of the predicted interlayer state. The NEXAFS data illustrate the rapid evolution of the electronic structure with the increased number of layers.
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Affiliation(s)
- D Pacilé
- Istituto Nazionale di Fisica Nucleare (INFN) and Dipartimento di Fisica Università della Calabria, 87036 Arcavacata di Rende, Cosenza, Italy.
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43
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Meyer JC, Girit CO, Crommie MF, Zettl A. Imaging and dynamics of light atoms and molecules on graphene. Nature 2008; 454:319-22. [DOI: 10.1038/nature07094] [Citation(s) in RCA: 430] [Impact Index Per Article: 26.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2007] [Accepted: 05/07/2008] [Indexed: 11/09/2022]
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44
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Leich E, Haralambieva E, Zettl A, Chott A, Rüdiger T, Höller S, Müller-Hermelink HK, Ott G, Rosenwald A. Tissue microarray-based screening for chromosomal breakpoints affecting the T-cell receptor gene loci in mature T-cell lymphomas. J Pathol 2007; 213:99-105. [PMID: 17582237 DOI: 10.1002/path.2196] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The pathogenesis of mature T-cell non-Hodgkin lymphomas (T-NHLs) is poorly understood. Analogous to B-cell lymphomas, in which the immunoglobulin (IgH) receptor loci are frequently targeted by chromosomal translocations, the T-cell receptor (TCR) gene loci are affected by translocations in a subset of precursor T-cell malignancies. In a large-scale analysis of 245 paraffin-embedded mature T-NHLs, arranged in a tissue microarray format and using improved FISH assays for the detection of breakpoints in the TCRalpha/delta, TCRbeta, and TCRgamma loci, we provide evidence that mature T-NHLs other than T-cell prolymphocytic leukaemia (T-PLL) also occasionally show a chromosomal rearrangement that involves the TCRalpha/delta locus. In particular, one peripheral T-cell lymphoma (not otherwise specified, NOS) with the morphological variant of Lennert lymphoma displayed a chromosomal translocation t(14;19) involving the TCRalpha/delta and the BCL3 loci. A second case, an angio-immunoblastic T-cell lymphoma (AILT), carried an inv(14)(q11q32) affecting the TCRalpha/delta and IgH loci. FISH signal constellations as well as concomitant comparative genomic hybridization (CGH) data were also suggestive of the occurrence of an isochromosome 7, previously described to be pathognomonic for hepatosplenic T-cell lymphomas, in rare cases of enteropathy-type T-cell lymphoma.
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MESH Headings
- B-Cell Lymphoma 3 Protein
- Case-Control Studies
- Chromosome Breakage
- Chromosomes, Human, Pair 14
- Chromosomes, Human, Pair 19
- Chromosomes, Human, Pair 7
- Gene Expression Profiling
- Gene Rearrangement, T-Lymphocyte
- Gene Rearrangement, alpha-Chain T-Cell Antigen Receptor
- Gene Rearrangement, delta-Chain T-Cell Antigen Receptor
- Genes, T-Cell Receptor
- Humans
- Immunoglobulin Heavy Chains/genetics
- In Situ Hybridization, Fluorescence
- Lymphoma, T-Cell/genetics
- Oligonucleotide Array Sequence Analysis
- Paraffin Embedding
- Proto-Oncogene Proteins/genetics
- Transcription Factors/genetics
- Translocation, Genetic
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Affiliation(s)
- E Leich
- Institute of Pathology, University of Würzburg, Germany
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45
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Nagel S, Leich E, Quentmeier H, Meyer C, Kaufmann M, Drexler HG, Zettl A, Rosenwald A, MacLeod RAF. Amplification at 7q22 targets cyclin-dependent kinase 6 in T-cell lymphoma. Leukemia 2007; 22:387-92. [PMID: 17989712 DOI: 10.1038/sj.leu.2405028] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Recurrent chromosomal aberrations in hematopoietic tumors target genes involved in pathogenesis. Their identification and functional characterization are therefore important for the establishment of rational therapies. Here, we investigated genomic amplification at 7q22 in the T-cell lymphoma cell line SU-DHL-1 belonging to the subtype of anaplastic large-cell lymphoma (ALCL). Cytogenetic analysis mapped this amplicon to 86-95 Mb. Copy-number determination quantified the amplification level at 5- to 6-fold. Expression analysis of genes located within this region identified cyclin-dependent kinase 6 (CDK6) as a potential amplification target. In comparison with control cell lines, SU-DHL-1 expressed considerably higher levels of CDK6. Functionally, SU-DHL-1 cells exhibited reduced sensitivity to rapamycin treatment, as indicated by cell growth and cell cycle analysis. Rapamycin reportedly inhibits degradation of the CDK inhibitor p27 with concomitant downregulation of cyclin D3, implying a proliferative advantage for CDK6 overexpression. Amplification of the CDK6 locus was analyzed in primary T-cell lymphoma samples and, while detected infrequently in those classified as ALCL (1%), was detected in 23% of peripheral T-cell lymphomas not otherwise specified. Taken together, analysis of the 7q22 amplicon identified CDK6 as an important cell cycle regulator in T-cell lymphomas, representing a novel potential target for rational therapy.
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Affiliation(s)
- S Nagel
- Department of Human and Animal Cell Cultures, DSMZ, Braunschweig, Germany.
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46
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Abstract
We have constructed a fully functional, fully integrated radio receiver from a single carbon nanotube. The nanotube serves simultaneously as all essential components of a radio: antenna, tunable band-pass filter, amplifier, and demodulator. A direct current voltage source, as supplied by a battery, powers the radio. Using carrier waves in the commercially relevant 40-400 MHz range and both frequency and amplitude modulation techniques, we demonstrate successful music and voice reception.
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Affiliation(s)
- K Jensen
- Department of Physics, Center of Integrated Nanomechanical Systems, University of California at Berkeley, Berkeley, California 94720, USA
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47
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Abstract
HISTORY AND ADMISSION FINDINGS A 44-year-old woman was on long-term immunosuppressive therapy with leflunomide and adalimumab for rheumatoid arthritis. She was admitted to the emergency room with diffuse abdominal pain of sudden onset. On physical examination she had rebound tenderness in all four abdominal quadrants. INVESTIGATIONS The white blood cell count was 3300/l, C-reactive protein 25 mg/dl and serum lactate 10 mmol/l. Abdominal computed tomography revealed a diffusely thickened gastric wall and ascites. At explorative laparotomy 1000 ml of a cloudy peritoneal fluid were aspirated and found to be negative for bacteria. But a culture of a mesenterial smear grew streptococci group A. Intra-operative endoscopy showed extensive hemorrhagic gastritis. Because there was no perforation or transmural necrosis gastric resection was not performed. DIAGNOSIS, TREATMENT AND COURSE Diffuse thickening of the gastric wall, extended mucosal necrosis and the peritoneal finding of streptococci in an immunocompromised patient suggested the diagnosis of phlegmonous gastritis. On treatment with antibiotics and proton pump inhibitor the patient made a slow recovery over the following eight weeks. Nine months after the event an asymptomatic antral stricture was noticed at follow-up gastroscopy. CONCLUSION Phlegmonous gastritis is a rare but life-threatening complication in immunosuppressed patients.
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Affiliation(s)
- W Scheppach
- Medizinische Klinik mit Schwerpunkt Gastroenterologie/Rheumatologie, Juliusspital Würzburg, Würzburg, Germany.
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48
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Abstract
We find that the high thermal conductivity of carbon nanotubes remains intact under severe structural deformations while the corresponding electrical resistance and thermoelectric power show compromised responses. Similar robust thermal transport against bending is found for boron nitride nanotubes. Surprisingly, for both systems the phonon mean free path exceeds the characteristic length of structural ripples induced by bending and approaches the theoretical limit set by the radius of curvature. The robustness of heat conduction in nanotubes refines the ultimate limit that is far beyond the reach of ordinary materials.
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Affiliation(s)
- C W Chang
- Department of Physics, University of California at Berkeley, California 94720, USA.
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49
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Abstract
Technologies for introducing molecules into living cells are vital for probing the physical properties and biochemical interactions that govern the cell's behavior. Here, we report the development of a nanoscale cell injection system (termed the nanoinjector) that uses carbon nanotubes to deliver cargo into cells. A single multiwalled carbon nanotube attached to an atomic force microscope (AFM) tip was functionalized with cargo via a disulfide-based linker. Penetration of cell membranes with this "nanoneedle" was controlled by the AFM. The following reductive cleavage of the disulfide bonds within the cell's interior resulted in the release of cargo inside the cells, after which the nanoneedle was retracted by AFM control. The capability of the nanoinjector was demonstrated by injection of protein-coated quantum dots into live human cells. Single-particle tracking was used to characterize the diffusion dynamics of injected quantum dots in the cytosol. This technique causes no discernible membrane or cell damage, and can deliver a discrete number of molecules to the cell's interior without the requirement of a carrier solvent.
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Affiliation(s)
- Xing Chen
- Departments of *Chemistry
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720
| | - Andras Kis
- Physics and
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720
| | - A. Zettl
- Physics and
- Center of Integrated Nanomechanical Systems, University of California, Berkeley, CA 94720; and
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720
- To whom correspondence may be addressed. E-mail: or
| | - Carolyn R. Bertozzi
- Departments of *Chemistry
- Molecular and Cell Biology
- **Howard Hughes Medical Institute, and
- Molecular Foundry and
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720
- To whom correspondence may be addressed. E-mail: or
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50
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Völker HU, Mühlmeier G, Maier H, Kraft K, Müller-Hermelink HK, Zettl A. True malignant mixed tumour (carcinosarcoma) of submandibular gland--a rare neoplasm of monoclonal origin? Histopathology 2007; 50:795-8. [PMID: 17376173 DOI: 10.1111/j.1365-2559.2007.02646.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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