| 1. |
- Kristan, Matej, et al.
(författare)
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The Ninth Visual Object Tracking VOT2021 Challenge Results
- 2021
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Ingår i: 2021 IEEE/CVF INTERNATIONAL CONFERENCE ON COMPUTER VISION WORKSHOPS (ICCVW 2021). - : IEEE COMPUTER SOC. - 9781665401913 ; , s. 2711-2738
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Konferensbidrag (refereegranskat)abstract
- The Visual Object Tracking challenge VOT2021 is the ninth annual tracker benchmarking activity organized by the VOT initiative. Results of 71 trackers are presented; many are state-of-the-art trackers published at major computer vision conferences or in journals in recent years. The VOT2021 challenge was composed of four sub-challenges focusing on different tracking domains: (i) VOT-ST2021 challenge focused on short-term tracking in RGB, (ii) VOT-RT2021 challenge focused on "real-time" short-term tracking in RGB, (iii) VOT-LT2021 focused on long-term tracking, namely coping with target disappearance and reappearance and (iv) VOT-RGBD2021 challenge focused on long-term tracking in RGB and depth imagery. The VOT-ST2021 dataset was refreshed, while VOT-RGBD2021 introduces a training dataset and sequestered dataset for winner identification. The source code for most of the trackers, the datasets, the evaluation kit and the results along with the source code for most trackers are publicly available at the challenge website(1).
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| 2. |
- Zhao, Jie, et al.
(författare)
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A Sequential Process of Graphene Exfoliation and Site-Selective Copper/Graphene Metallization Enabled by Multifunctional 1-Pyrenebutyric Acid Tetrabutylammonium Salt
- 2019
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Ingår i: ACS Applied Materials and Interfaces. - : American Chemical Society (ACS). - 1944-8244 .- 1944-8252. ; 11:6, s. 6448-6455
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Tidskriftsartikel (refereegranskat)abstract
- This paper reports a procedure leading to shear exfoliation of pristine few-layer graphene flakes in water and subsequent site-selective formation of Cu/graphene films on polymer substrates, both of which are enabled by employing the water soluble 1-pyrenebutyric acid tetrabutylammonium salt (PyB-TBA). The exfoliation with PyB-TBA as an enhancer leads to as-deposited graphene films dried at 90 °C that are characterized by electrical conductivity of ∼110 S/m. Owing to the good affinity of the tetrabutylammonium cations to the catalyst PdCl42–, electroless copper deposition selectively in the graphene films is initiated, resulting in a self-aligned formation of highly conductive Cu/graphene films at room temperature. The excellent solution-phase and low-temperature processability, self-aligned copper growth, and high electrical conductivity of the Cu/graphene films have permitted fabrication of several electronic circuits on plastic foils, thereby indicating their great potential in compliant, flexible, and printed electronics.
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| 3. |
- Kristan, Matej, et al.
(författare)
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The Visual Object Tracking VOT2015 challenge results
- 2015
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Ingår i: Proceedings 2015 IEEE International Conference on Computer Vision Workshops ICCVW 2015. - : IEEE. - 9780769557205 ; , s. 564-586
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Konferensbidrag (refereegranskat)abstract
- The Visual Object Tracking challenge 2015, VOT2015, aims at comparing short-term single-object visual trackers that do not apply pre-learned models of object appearance. Results of 62 trackers are presented. The number of tested trackers makes VOT 2015 the largest benchmark on short-term tracking to date. For each participating tracker, a short description is provided in the appendix. Features of the VOT2015 challenge that go beyond its VOT2014 predecessor are: (i) a new VOT2015 dataset twice as large as in VOT2014 with full annotation of targets by rotated bounding boxes and per-frame attribute, (ii) extensions of the VOT2014 evaluation methodology by introduction of a new performance measure. The dataset, the evaluation kit as well as the results are publicly available at the challenge website(1).
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| 4. |
- Lanner, Johanna T., et al.
(författare)
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Knockdown of TRPC3 with siRNA coupled to carbon nanotubes results in decreased insulin-mediated glucose uptake in adult skeletal muscle cells
- 2009
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Ingår i: The FASEB Journal. - : Wiley. - 0892-6638 .- 1530-6860. ; 23:6, s. 1728-1738
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Tidskriftsartikel (refereegranskat)abstract
- The involvement of Ca2+ in the insulin-mediated signaling cascade, resulting in glucose uptake in skeletal muscle, is uncertain. Here, we test the hypothesis that Ca2+ influx through canonical transient receptor potential 3 (TRPC3) channels modulates insulin-mediated glucose uptake in adult skeletal muscle. Experiments were performed on adult skeletal muscle cells of wild-type (WT) and obese, insulin-resistant ob/ob mice. Application of the diacylglycerol analog 1-oleyl-2-acetyl-sn-glycerol (OAG) induced a nonselective cation current, which was inhibited by the addition of anti-TRPC3 antibody in the patch pipette and smaller in ob/ob than in WT cells. Knockdown of TRPC3, using a novel technique based on small interfering RNA (siRNA) coupled to functionalized carbon nanotubes, resulted in pronounced (similar to 70%) decreases in OAG-induced Ca2+ influx and insulin-mediated glucose uptake. TRPC3 and the insulin-sensitive glucose transporter 4 (GLUT4) coimmunoprecipitated, and immunofluorescence staining showed that they were colocalized in the proximity of the transverse tubular system, which is the predominant site of insulin-mediated glucose transport in skeletal muscle. In conclusion, our results indicate that TRPC3 interacts functionally and physically with GLUT4, and Ca2+ influx through TRPC3 modulates insulin-mediated glucose uptake. Thus, TRPC3 is a potential target for treatment of insulin-resistant conditions.-Lanner, J. T., Bruton, J. D., Assefaw-Redda, Y., Andronache, Z., Zhang, S.- J., Severa, D., Zhang, Z.- B., Melzer, W., Zhang, S.-L., Katz, A., Westerblad, H. Knockdown of TRPC3 with siRNA coupled to carbon nanotubes results in decreased insulin-mediated glucose uptake in adult skeletal muscle cells. FASEB J. 23, 1728-1738 (2009)
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| 5. |
- Li, Jiantong, et al.
(författare)
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Ink-jet printed thin-film transistors with carbon nanotube channels shaped in long strips
- 2011
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Ingår i: Journal of Applied Physics. - : AIP Publishing. - 0021-8979 .- 1089-7550. ; 109:8, s. 084915-
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Tidskriftsartikel (refereegranskat)abstract
- The present work reports on the development of a class of sophisticated thin-film transistors (TFTs) based on ink-jet printing of pristine single-walled carbon nanotubes (SWCNTs) for the channel formation. The transistors are manufactured on oxidized silicon wafers and flexible plastic substrates at ambient conditions. For this purpose, ink-jet printing techniques are developed with the aim of high-throughput production of SWCNT thin-film channels shaped in long strips. Stable SWCNT inks with proper fluidic characteristics are formulated by polymer addition. The present work unveils, through Monte Carlo simulations and in light of heterogeneous percolation, the underlying physics of the superiority of long-strip channels for SWCNT TFTs. It further predicts the compatibility of such a channel structure with ink-jet printing, taking into account the minimum dimensions achievable by commercially available printers. The printed devices exhibit improved electrical performance and scalability as compared to previously reported ink-jet printed SWCNT TFTs. The present work demonstrates that ink-jet printed SWCNT TFTs of long-strip channels are promising building blocks for flexible electronics.
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| 6. |
- Liu, Zhiying, et al.
(författare)
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On Gate Capacitance of Nanotube Networks
- 2011
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Ingår i: IEEE Electron Device Letters. - : IEEE. - 0741-3106 .- 1558-0563. ; 32:5, s. 641-643
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Tidskriftsartikel (refereegranskat)abstract
- This letter presents a systematic investigation of the gate capacitance C-G of thin-film transistors (TFTs) based on randomly distributed single-walled carbon nanotubes (SWCNTs) in the channel. In order to reduce false counting of SWCNTs that do not contribute to current conduction, C-G is directly measured on the TFTs using a well-established method for MOSFETs. Frequency dispersion of C-G is observed, and it is found to depend on the percolation behavior in SWCNT networks. This dependence can be accounted for using an RC transmission line model. These results are of important implications for the determination of carrier mobility in nanoparticle-based TFTs.
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| 7. |
- Zhang, Shuai, et al.
(författare)
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Large-Scale and Low-Cost Motivation of Nitrogen-Doped Commercial Activated Carbon for High-Energy-Density Supercapacitor
- 2019
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Ingår i: ACS Applied Energy Materials. - : American Chemical Society (ACS). - 2574-0962. ; 2:6, s. 4234-4243
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Tidskriftsartikel (refereegranskat)abstract
- The growing requirement for high-performance energy-storage devices has spurred the development of supercapacitors, but the low energy density remains a technical hurdle. In this work, porous nitrogen-doped activated carbon (NAC) is prepared on a large scale from commercial activated carbon (AC) and inexpensive chemicals by a one-step method. The NAC material with 3.1 wt % nitrogen has a high specific surface area of 1186 m(2) g(-1) and shows a specific capacitance of 427 F g(-1) in a symmetric cell with an aqueous electrolyte. 98.2% of the capacity is reserved after 20 000 cycles at 20 A g(-1). The energy densities of the NAC are 17.2 and 87.8 Wh kg(-1) in acidic and organic electrolytes, respectively. Moreover, this simple process is readily scalable to address commercial demand and can be extended to the motivation of a variety of carbon based materials with poor capacitances.
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| 8. |
- Zhang, Zhibin, et al.
(författare)
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Reversible surface functionalisation of carbon nanotubes for fabrication of field effect transistors
- 2005
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Ingår i: Applied Physics Letters. - : AIP Publishing. - 0003-6951 .- 1077-3118. ; 87
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Tidskriftsartikel (refereegranskat)abstract
- Evidence of the adsorption of sodium dodecyl sulfate (SDS) residuals on single-walled carbon nanotubes (SWNTs) is shown using x-ray photoelectron spectroscopy. The adsorption of SDS on semiconducting SWNTs (s-SWNTs) is believed to result in deposition and alignment of s-SWNTs between predefined electrode pairs using ac dielectrophoresis. However, the presence of SDS on SWNTs degrades electrical properties of the fabricated devices. Attempts at surface cleaning, aimed at removal of the SDS residuals and formation of an improved contact between the SWNTs and the metal, are described.
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| 9. |
- Ahlberg, Patrik, et al.
(författare)
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Defect formation in graphene during low-energy ion bombardment
- 2016
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Ingår i: APL Materials. - : AIP Publishing. - 2166-532X. ; 4:4
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Tidskriftsartikel (refereegranskat)abstract
- This letter reports on a systematic investigation of sputter induced damage in graphene caused by low energy Ar+ ion bombardment. The integral numbers of ions per area (dose) as well as their energies are varied in the range of a few eV's up to 200 eV. The defects in the graphene are correlated to the dose/energy and different mechanisms for the defect formation are presented. The energetic bombardment associated with the conventional sputter deposition process is typically in the investigated energy range. However, during sputter deposition on graphene, the energetic particle bombardment potentially disrupts the crystallinity and consequently deteriorates its properties. One purpose with the present study is therefore to demonstrate the limits and possibilities with sputter deposition of thin films on graphene and to identify energy levels necessary to obtain defect free graphene during the sputter deposition process. Another purpose is to disclose the fundamental mechanisms responsible for defect formation in graphene for the studied energy range.
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| 10. |
- Ahlberg, Patrik, 1985-
(författare)
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Graphene Implementation Study in Semiconductor Processing
- 2016
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Graphene, with its two-dimensional nature and unique properties, has for over a decade captured enormous interests in both industry and academia. This work tries to answer the question of what would happen to graphene when it is subjected to various processing conditions and how this would affect the graphene functionality. The focus is placed on its ability to withstand different thin-film deposition environments with regard to the implementation of graphene in two application areas: as a diffusion barrier and in electronic devices.With single-layer graphene films grown in-house by means of chemical vapor deposition (CVD), four techniques among the well-established thin-film deposition methods are studied in detail: atomic layer deposition (ALD), evaporation, sputter-deposition and spray-deposition. And in this order, these methods span a large range of kinetic impact energies from low to high. Graphene is known to have a threshold displacement energy of 22 eV above which carbon atoms are ejected from the lattice. Thus, ALD and evaporation work with energies below this threshold, while sputtering and spraying may involve energies above. The quality of the graphene films undergone the various depositions is mainly evaluated using Raman spectroscopy.Spray deposition of liquid alloy Ga-In-Sn is shown to require a stack of at least 4 layers of graphene in order to act as an effective barrier to the Ga diffusion after the harsh spray-processing. Sputter-deposition is found to benefit from low substrate temperature and high chamber pressure (thereby low kinetic impact energy) so as to avoid damaging the graphene. Reactive sputtering should be avoided. Evaporation is non-invasiveness with low kinetic impact energy and graphene can be subjected to repeated evaporation and removal steps without losing its integrity. With ALD, the effects on graphene are of different nature and they are investigated in the field-effect-transistor (FET) configuration. The ALD process for deposition of Al2O3 films is found to remove undesired dopants from the prior processing and the Al2O3 films are shown to protect the graphene channel from doping by oxygen. When the substrate is turned hydrophobic by chemical treatment prior to graphene transfer-deposition, a unipolar transistor behavior is obtained.
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| 11. |
- Cardenas, J. F., et al.
(författare)
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Structure and Mesoscopic Characterization of Laser Ablated Carbon Nanoparticles in Water by Raman Scattering
- 2016
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Ingår i: Optical Micro- And Nanometrology VI. - : SPIE. - 9781510601352
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Konferensbidrag (refereegranskat)abstract
- Carbon nanoparticles (CNPs) have been synthesized by laser ablation of polycrystalline graphite in water using a pulsed Nd:YAG laser (1064 nm) with a width of 8 ns and characterized by Raman spectroscopy and atomic force microscopy. The characteristic sizes of CNPs in the supernantant are in the range of 1-2 nm and 10-50 nm with structures corresponding to amorphous and sp(2)-carbon, respectively. Raman spectra of the CNPs from the supernatant reveal a background as a consequence of photoluminescence. The absence of a distinct Raman peak associated with hydrogenated amorphous carbon (a-C:H) suggests an other source for the photolominescence than a-C:H. Large (10-100 mu m) CNPs removed from the surface are unmodified (in structure and topology) by the laser as confirmed by Raman analysis.
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| 12. |
- Chen, Libo, et al.
(författare)
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Spike timing–based coding in neuromimetic tactile system enables dynamic object classification
- 2024
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Ingår i: Science. - 0036-8075. ; 384, s. 660-665
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Tidskriftsartikel (refereegranskat)abstract
- Rapid processing of tactile information is essential to human haptic exploration and dexterous object manipulation. Conventional electronic skins generate frames of tactile signals upon interaction with objects. Unfortunately, they are generally ill-suited for efficient coding of temporal information and rapid feature extraction. In this work, we report a neuromorphic tactile system that uses spike timing, especially the first-spike timing, to code dynamic tactile information about touch and grasp. This strategy enables the system to seamlessly code highly dynamic information with millisecond temporal resolution on par with the biological nervous system, yielding dynamic extraction of tactile features. Upon interaction with objects, the system rapidly classifies them in the initial phase of touch and grasp, thus paving the way to fast tactile feedback desired for neuro-robotics and neuro-prosthetics.
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| 13. |
- Chen, Zhibin, et al.
(författare)
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Summary of the 3rd International Workshop on Gas-Dynamic Trap based Fusion Neutron Source (GDT-FNS)
- 2022
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Ingår i: Nuclear Fusion. - : IOP Publishing. - 0029-5515 .- 1741-4326. ; 62:6
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Tidskriftsartikel (refereegranskat)abstract
- The 3rd International Workshop on Gas-Dynamic Trap-based Fusion Neutron Source (GDT-FNS) was held through the hybrid mode on 13-14 September 2021 in Hefei, China, jointly organized by the Hefei Institutes of Physical Science (HFIPS), Chinese Academy of Sciences (CAS), and the Budker Institute of Nuclear Physics (BINP), Russian Academy of Sciences (RAS). It followed the 1st GDT-FNS Workshop held in November 2018 in Hefei, China, and the 2nd taking place in November 2019 in Novosibirsk, Russian Federation. With the financial support from CAS and China Association for Science and Technology (CAST), this workshop was attended by more than 80 participants representing 20 institutes and universities from seven countries, with oral presentations broadcast via the Zoom conferencing system. Twenty-two presentations were made with topics covering design and key technologies, simulation and experiments, steady-state operation, status of the ALIANCE project, multi applications of neutron sources, and other concepts (Tokamaks, Mirrors, FRC, Plasma Focus, etc). The workshop consensus was made including the establishment of the ALIANCE International Working Group. The next GDT-FNS workshop is planned to be held in May 2022 in Novosibirsk.
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| 14. |
- Jarmar, T., et al.
(författare)
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Germanium-induced texture and preferential orientation of NiSi1-xGex layers on Si1-xGex
- 2004
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Ingår i: Physical Review B. Condensed Matter and Materials Physics. - 1098-0121 .- 1550-235X. ; 70:23, s. 1-11
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Tidskriftsartikel (refereegranskat)abstract
- NiSi1-xGex films on compressively strained as well as relaxed undoped Si1-xGex epitaxially grown substrates with x=0.06-0.30 on Si(001) wafers have been studied with respect to the relative orientation of film and substrate after annealing at temperatures in the range 400-850 degreesC. Using x-ray diffraction, transmission electron microscopy, and pole-figure measurements, it was found that only the monogermanosilicide phase formed above 450 degreesC and was the only phase still at 850 degreesC. New information regarding the effects of Ge on the silicidation of Ni was also found. Thus, the preferred plane parallel to the surface is (013). Compared to NiSi, Ge suppresses the development of the other planes parallel to the surface except (013). Within this plane, the orientations of the grains pile up in such a way that the configuration NiSi1-xGex[100]//Si1-xGex[100] is avoided, which in the pole-figures leads to broad peaks in-between the substrate [100] and [010]. In addition, peaks indicating the epitaxial alignment NiSi0.8Ge0.2(+/-21-1) or (+/-2-11)//Si0.8Ge0.2(+/-2+/-20) coupled with NiSi0.8Ge0.2(+/-100)approximate to//Si0.8Ge0.2(+/-100) or (0+/-10) were found. Fine structure in the broad peaks is found to be due to lateral epitaxial alignments between grains along their common grain boundary. Based on the nonexistence of NiGe2, the observations are interpreted in terms of Ge preventing the formation of certain Ni-Ge bonds at the interface between NiSi1-xGex and the Si1-xGex substrate.
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| 15. |
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| 16. |
- Li, Jiantong, et al.
(författare)
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Contact-electrode insensitive rectifiers based on carbon nanotube network transistors
- 2008
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Ingår i: IEEE Electron Device Letters. - : Institute of Electrical and Electronics Engineers (IEEE). - 0741-3106 .- 1558-0563. ; 29:5, s. 500-502
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Tidskriftsartikel (refereegranskat)abstract
- This letter presents rectifiers based on the diode connection of carbon nanotube network (CNN) transistors. Despite a low density of carbon nanotubes in the CNNs, the devices can achieve excellent performance with a forward/reverse current ratio reaching 10(5). By casting nanotube suspension on oxidized Si substrates with predefined electrodes, CNN-based field-effect transistors are readily prepared. By short-circuiting the source and gate terminals, CNN-based rectifiers are realized with the rectification characteristics independent of whether Pd or Al is employed as the contact electrodes. This independence is especially attractive for applications of CNN-based transistors/rectifiers in flexible electronics with various printing techniques.
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| 17. |
- Li, Jiantong, et al.
(författare)
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Distinguishing self-gated rectification action from ordinary diode rectification in back-gated carbon nanotube devices
- 2008
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Ingår i: Applied Physics Letters. - : AIP Publishing. - 0003-6951 .- 1077-3118. ; 92:133111
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Tidskriftsartikel (refereegranskat)abstract
- Self-gating leading to rectification action is frequently observed in two-terminal devices built from individual or networked single-walled carbon nanotubes (SWCNTs) on oxidized Si substrates. The current-voltage (I-V) curves of these SWCNT devices remain unaltered when switching the measurement probes. For ordinary diodes, the I-V curves are symmetric about the origin of the coordinates when exchanging the probes. Numerical simulations suggest that the self-gated rectification action should result from the floating semiconducting substrate which acts as a back gate. Self-gating effect is clearly not unique for SWCNT devices. As expected, it is absent for devices fabricated on insulating substrates.
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| 18. |
- Li, Jiantong, et al.
(författare)
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Improved electrical performance of carbon nanotube thin film transistors by utilizing composite networks
- 2008
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Ingår i: Applied Physics Letters. - : AIP Publishing. - 0003-6951 .- 1077-3118. ; 92:133103
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Tidskriftsartikel (refereegranskat)abstract
- This work presents a simple scheme of using composite carbon nanotube networks (c-CNNs) to significantly improve the electrical performance of long-channel thin film transistors based on single-walled carbon nanotubes (SWCNTs). Such c-CNNs comprise two sets of SWCNTs. A primary set consists of dense arrays of perfectly aligned long SWCNTs along the transistor channel direction. A secondary set is composed of short SWCNTs either randomly orientated or perpendicularly aligned with respect to the channel. While retaining a high on/off current ratio, the drive current in such c-CNNs is much higher than that in currently studied systems with single CNNs or SWCNT arrays.
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| 19. |
- Li, Jiantong, et al.
(författare)
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Percolation in random networks of heterogeneous nanotubes
- 2007
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Ingår i: Applied Physics Letters. - : AIP Publishing. - 0003-6951 .- 1077-3118. ; 91:253127
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Tidskriftsartikel (refereegranskat)abstract
- The electrical performance of random carbon nanotube network transistors is found by Monte Carlo simulation to strongly depend on the nature of the conduction path percolating the network. When the network is percolated only by semiconducting nanotube pathways (OSPs), the transistors can directly achieve both high on current and large on/off current ratio. Based on percolation theory, the present work predicts that there exist specific nanotube coverage domains within which OSP has the highest probability and becomes predominant. Simulation results show that the coverage domains depend on the network dimension, nanotube length, and the fraction of metallic nanotubes.
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| 20. |
- Liu, Zhiying, 1982-, et al.
(författare)
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Solution-Processed Logic Gates Based On Nanotube/Polymer Composite
- 2013
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Ingår i: IEEE Transactions on Electron Devices. - 0018-9383 .- 1557-9646. ; 60:8, s. 2542-2547
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Tidskriftsartikel (refereegranskat)abstract
- Hysteresis-free logic gates capable of operation at 100 kHz are fabricated basing on local-gate thin-film transistors with their channel featuring solution-processed composite films of single-walled carbon nanotubes (SWCNTs) and poly(9,9-dioctylfluorene-co-bithiophene) (F8T2). Using dip-coating for deposition of composite films, high-density SWCNTs are found to be embedded in an F8T2 layer and thus being kept from the underlying AlOx gate dielectric by a certain distance. The presence of the F8T2 interlayer effectively suppresses hysteresis although it also weakens the gate electrostatic control. The fabricated transistors are characterized by nil hysteresis, high carrier mobility, large ON/OFF current ratio, low operation voltage, small subthreshold swing, and remarkable scalability. These properties are crucial for the realization of the well-performing logic circuits.
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| 21. |
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| 22. |
- Majee, Subimal, 1984-, et al.
(författare)
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Production of transparent and conductive stable graphene ink for inkjet printing method
- 2015
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Konferensbidrag (refereegranskat)abstract
- Electrical interconnections are one of the main challenges in the printed electronics, to connect different functional units of an electronic device. With the progressive advancement of large area and low cost printed electronic devices on polymeric and paper substrates, the requirement for reliable interconnections with lower power consumption fabricated at low temperature is necessary. The conventional copper-based interconnections suffer severe problems in terms of cost efficiency when they are processed with photolithography technique. To replace the conventional metallic interconnections we have proposed printed interconnects with graphene inks. This is mainly motivated by two reasons. First, printing is a low-cost patterning approach which is performed at ordinary ambient condition. Printing of graphene proved to be a promising since it combines the attractive features of graphene and the cost effective printing methods (ink-jet printing, nozzle printing, spray printing) which enable additive patterning, direct writing, scalability to large area manufacturing. In order to facilitate the inkjet printing process, the graphene solution needs to be highly stable, uniform and should contain smaller sheet sizes (~ 1 micro meter) because of the limitation of the nozzle size of inkjet printing machine. In this work we have proposed a cost-effective approach for large-scale production of printable stable graphene suspension by liquid-phase shear exfoliation of graphite for printed electronics application. The process is scalable and requires shorter processing time compared to the other existing exfoliation methods. Graphene sheets have been exfoliated from graphite flakes in a solvent, cyclohexanone with ethyl cellulose as stabilizer. The graphene based solution prepared after several optimizations leads to a stable ink for more than six months without any sedimentation. The initial studies confirmed the production of graphene films with average sheet thickness of 10 to 20 nm and without any agglomeration with sheet sizes less than 1 micro meter. The rheological properties, such as, viscosity, of the produced graphene ink has been carefully tuned in order for successful inkjet printing process. Highly conductive and transparent (~70 % in the visible region) interconnections have been developed after several inkjet printing steps.
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| 23. |
- Sampson, Joshua N., et al.
(författare)
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Analysis of Heritability and Shared Heritability Based on Genome-Wide Association Studies for 13 Cancer Types
- 2015
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Ingår i: Journal of the National Cancer Institute. - : Oxford University Press (OUP). - 0027-8874 .- 1460-2105. ; 107:12
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Tidskriftsartikel (refereegranskat)abstract
- Background: Studies of related individuals have consistently demonstrated notable familial aggregation of cancer. We aim to estimate the heritability and genetic correlation attributable to the additive effects of common single-nucleotide polymorphisms (SNPs) for cancer at 13 anatomical sites. Methods: Between 2007 and 2014, the US National Cancer Institute has generated data from genome-wide association studies (GWAS) for 49 492 cancer case patients and 34 131 control patients. We apply novel mixed model methodology (GCTA) to this GWAS data to estimate the heritability of individual cancers, as well as the proportion of heritability attributable to cigarette smoking in smoking-related cancers, and the genetic correlation between pairs of cancers. Results: GWAS heritability was statistically significant at nearly all sites, with the estimates of array-based heritability, h(l)(2), on the liability threshold (LT) scale ranging from 0.05 to 0.38. Estimating the combined heritability of multiple smoking characteristics, we calculate that at least 24% (95% confidence interval [CI] = 14% to 37%) and 7% (95% CI = 4% to 11%) of the heritability for lung and bladder cancer, respectively, can be attributed to genetic determinants of smoking. Most pairs of cancers studied did not show evidence of strong genetic correlation. We found only four pairs of cancers with marginally statistically significant correlations, specifically kidney and testes (rho = 0.73, SE = 0.28), diffuse large B-cell lymphoma (DLBCL) and pediatric osteosarcoma (rho = 0.53, SE = 0.21), DLBCL and chronic lymphocytic leukemia (CLL) (rho = 0.51, SE = 0.18), and bladder and lung (rho = 0.35, SE = 0.14). Correlation analysis also indicates that the genetic architecture of lung cancer differs between a smoking population of European ancestry and a nonsmoking Asian population, allowing for the possibility that the genetic etiology for the same disease can vary by population and environmental exposures. Conclusion: Our results provide important insights into the genetic architecture of cancers and suggest new avenues for investigation.
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| 24. |
- Seger, Johan, et al.
(författare)
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Influence of a Si layer intercalated between Si0.75Ge0.25 and Ni on the behavior of the resulting NiSi1-uGeu film
- 2004
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Ingår i: Journal of Applied Physics. - : AIP Publishing. - 0021-8979 .- 1089-7550. ; 96:12, s. 7179-7182
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Tidskriftsartikel (refereegranskat)abstract
- The interaction of Ni films with epitaxially grown Si-capped and not capped Si0.75Ge0.25 layers on Si(100) at 500degreesC leads to the formation of NiSi1-uGeu films as a bilayer NiSi on NiSi0.75Ge0.25 with a rather clear compositional boundary. In the absence of a Si cap at the surface, NiSi0.75Ge0.25 is formed on NiSi. Epitaxy of NiSi on NiSi0.75Ge0.25, and vice versa, occurs across the compositional boundary. The crystallographic orientation of the NiSi1-uGeu films is strongly affected by the initial layer thicknesses and the layer sequence. Without a Si cap, the NiSi1-uGeu films show an increased fiber texture with increasing Si0.75Ge0.25 thickness. In the presence of a Si cap, on the other hand, the texture collapses into a random orientation already for thin caps. Rapid diffusion of Ge at 500degreesC results in the presence of some Ge at the NiSi/Si interface for a NiSi0.75Ge0.25/NiSi/Si structure. This diffusion is accompanied by an increased roughness at the NiSi/Si interface, as compared to the quite flat NiSi/Si interface in the absence of Ge. For thin Si caps, severe interface roughening with thick NiSi0.75Ge0.25 grains protruding deeply into the remaining Si0.75Ge0.25 is observed.
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| 25. |
- Seger, Johan, et al.
(författare)
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Morphological instability of NiSi1-uGeu on single-crystal and polycrystalline Si1-xGex
- 2004
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Ingår i: Journal of Applied Physics. - : AIP Publishing. - 0021-8979 .- 1089-7550. ; 96:4, s. 1919-1928
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Tidskriftsartikel (refereegranskat)abstract
- The morphological stability of NiSi1-uGeu ternary alloy films formed by reacting Ni with single-crystal (sc) and polycrystalline (poly) Si1-xGeu is studied (u can be different from x). The agglomeration of NiSi1-uGeu films on Si0.7Ge0.3 occurs at 550degreesC after rapid thermal processing for 30 s, independently of the crystallinity of the Si1-xGeu. This behavior distinctly different from NiSi: NiSi films on poly-Si display a poorer morphological stability and degrade at lower temperatures than NiSi on sc-Si. On strained Si1-xGex, the presence of Ge simultaneously gives rise to two effects of different origin: mechanical and thermodynamic. The main driving forces behind the agglomeration of NiSi1-uGeu on sc-Si1-xGex are found to be the stored strain energy in the Si1-xGex and the larger (absolute) free energy of formation of NiSi compared to NiGe. The latter constitutes the principal driving force behind the agglomeration of NiSi1-uGeu on poly-Si1-xGex and is not affected by the degree of crystallinity of Si1-xGex. The total free-energy change also includes terms corresponding to the entropy of mixing of Si and Ge in both Si1-xGex and NiSi1-uGeu. Calculations show that the strain energy and the total free-energy change can be 5-7 times (with 30 at.% Ge) the surface/interface and grain-boundary energies in a NiSi film or the grain-boundary energy in an underlying poly-Si. These latter energies are responsible for the agglomeration of NiSi on sc- and poly-Si. The agglomeration takes place primarily via the interdiffusion of Si and Ge between Si1-xGex and NiSi1-uGeu. A structure likely to improve the stability of NiSi1-uGeu/Si1-xGex is discussed.
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