In this review, we summarize solution-processed oxide thin-film transistors (TFTs) researches based on our fulfillments. We describe the fundamental studies of precursor composition effects at the ...beginning in order to figure out the role of each component in oxide semiconductors, and then present low temperature process for the adoption of flexible devices. Moreover, channel engineering for high performance and reliability of solution-processed oxide TFTs and various coating methods: spin-coating, inkjet printing, and gravure printing are also presented. The last topic of this review is an overview of multi-functional solution-processed oxide TFTs for various applications such as photodetector, biosensor, and memory.
We report graphitic carbon growth on crystalline and amorphous oxide substrates by using carbon molecular beam epitaxy. The films are characterized by Raman spectroscopy and X-ray photoelectron ...spectroscopy. The formations of nanocrystalline graphite are observed on silicon dioxide and glass, while mainly
sp
2
amorphous carbons are formed on strontium titanate and yttria-stabilized zirconia. Interestingly, flat carbon layers with high degree of graphitization are formed even on amorphous oxides. Our results provide a progress toward direct graphene growth on oxide materials.
PACS
: 81.05.uf; 81.15.Hi; 78.30.Ly.
Background
Reconstruction of amino acid sequences from assembled transcriptome is of interest in personalized medicine, for example, to predict drug-target (or protein-protein) interaction ...considering individual’s genomic variations. Most of the existing transcriptome assemblers, however, seems not well suited for this purpose.
Methods
In this work, we present StringFix, an annotation guided transcriptome assembly and protein sequence reconstruction software tool that takes genome-aligned reads and the annotations associated to the reference genome as input. The tool ‘fixes’ the pre-annotated transcript sequence by taking small variations into account, finally to produce possible amino acid sequences that are likely to exist in the test tissue.
Results
The results show that, using outputs from existing reference-based assemblers as the input GTF-guide, StringFix could reconstruct amino acid sequences more precisely with higher sensitivity than direct generation using the recovered transcripts from all the assemblers we tested.
Conclusion
By using StringFix with the existing reference-based assemblers, one can recover not only a novel transcripts and isoforms but also the possible amino acid sequence stemming from them.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
We developed a method to improve the electrical performance and stability of passivated amorphous In–Ga–Zn–O thin-film transistors by simultaneous ultraviolet and thermal (SUT) treatment. SUT ...treatment was carried out on fully fabricated thin-film transistors, including deposited source/drain and passivation layers. Ultraviolet (UV) irradiation disassociated weak and diatomic chemical bonds and generated defects, and simultaneous thermal annealing rearranged the defects. The SUT treatment promoted densification and condensation of the channel layer by decreasing the concentration of oxygen-vacancy-related defects and increasing the concentration of metal–oxide bonds. The SUT-treated devices exhibited improved electrical properties compared to nontreated devices: field-effect mobility increased from 5.46 to 13.36 V·s, sub-threshold swing decreased from 0.49 to 0.32 V/decade, and threshold voltage shift (for positive bias temperature stress) was reduced from 5.1 to 1.9 V.
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In this paper, we propose a hybrid beam-forming and beam-switching technique for OFDM based wireless personal area networks (WPAN). In order to compromise between performance and computational cost ...and overheads for the channel side information feedback, the proposed system employs hybrid beam-forming and beam-switching, where the block beam-switching using a predefined beam codebook is used at the transmitter while the optimum per-subcarrier beam-forming is used at the receiver. To verify the performance of the proposed scheme, the effective SNR gain over the single antenna transmission system is investigated along with the spectral efficiency bound for some of the channels developed by the IEEE 802.15.3c task group. For comparison, the performance of the optimum per-subcarrier beam-forming and the block beam-switching are also examined.
Surface enhanced Raman spectroscopy (SERS) has been intensively investigated during the past decades for its enormous electromagnetic field enhancement near the nanoscale metallic surfaces. Chemical ...enhancement of SERS, however, remains rather elusive despite intensive research efforts, mainly due to the relatively complex enhancing factors and inconsistent experimental results. To study details of chemical enhancement mechanism, we prepared various low dimensional semiconductor substrates such as ZnO and GaN that were fabricated via metal organic chemical vapor deposition process. We used three kinds of molecules (4-MPY, 4-MBA, 4-ATP) as analytes to measure SERS spectra under non-plasmonic conditions to understand charge transfer mechanisms between a substrate and analyte molecules leading to chemical enhancement. We observed that there is a preferential route for charge transfer responsible for chemical enhancement, that is, there exists a dominant enhancement process in non-plasmonic SERS. To further confirm our idea of charge transfer mechanism, we used a combination of 2-dimensional transition metal dichalcogenide substrates and analyte molecules. We also observed significant enhancement of Raman signal from molecules adsorbed on 2-dimensional transition metal dichalcogenide surface that is completely consistent with our previous results. We also discuss crucial factors for increasing enhancement factors for chemical enhancement without involving plasmonic resonance.
This paper considers a belief propagation algorithm over pairwise graphical models to develop low-complexity iterative multiple-input multiple-output (MIMO) detectors. The pairwise graphical model is ...a bipartite graph where a pair of variable nodes are related by an observation node represented by the bivariate Gaussian function obtained by marginalizing the posterior joint probability density under the Gaussian input assumption. Specifically, we consider two types of pairwise models: the fully connected and ring-type. The pairwise graphs are sparse, compared with the conventional graphical model introduced by Bickson et al., insofar as the number of edges connected to an observation node (edge degree) is only two. Consequently, the computations are much easier than those of maximum likelihood (ML) detection, which are similar to the belief propagation (BP) that is run over the fully connected bipartite graph. The link level performance for non-Gaussian input is evaluated via simulations, and the results show the validity of the proposed algorithms. We also customize the algorithm with Gaussian input assumption to obtain the Gaussian BP run over the two pairwise graphical models, and for the ring-type, we prove its convergence to the linear minimum mean square error (MMSE) estimates. Since the maximum a posterior (MAP) estimator for Gaussian input is equivalent to the linear MMSE estimator, it shows the optimality of the scheme for Gaussian input.
Triple-negative breast cancer (TNBC) is a significant clinical challenge due to its aggressive nature and limited treatment options. In search of new treatment targets, not only single genes but also ...gene pairs involved in protein interactions, we explored the tumor microenvironment (TME) of TNBC from a retrospective point of view, using public single-cell RNA sequencing datasets. A High-resolution Cell type Annotation Tool, HiCAT, was used first to identify the cell type in 3-level taxonomies. Tumor cells were then identified based on the estimates of copy number variation. With the annotation results, differentially expressed genes were analyzed to find subtype-specific markers for each cell type, including tumor cells, fibroblast, and macrophage. Cell-cell interactions were also inferred for each cell type pair. Through integrative analysis, we could find unique TNBC markers not only for tumor cells but also for various TME components, including fibroblasts and macrophages. Specifically, twelve marker genes, including
and
, were identified for TNBC tumor cells. Another key finding of our study was the interaction between the
and
genes among TNBC tumor cells, suggesting that they are more tightly aggregated with each other than those of other subtypes, including normal epithelial cells. The overexpression of
in TNBC and its prognostic power were verified by using METABRIC, a large bulk RNA-seq dataset with clinical information. These findings not only corroborate previous hypotheses but also lay the foundation for a new structural understanding of TNBC, as revealed through our single-cell analysis workflow.
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We report a method for fabricating solution-processed quaternary In-Ga-Zn-O (IGZO) thin-film transistors (TFTs) at low annealing temperatures using a vertical diffusion technique (VDT). The VDT is a ...deposition process for spin-coating binary and ternary oxide layers consecutively and annealing at once. With the VDT, uniform and dense quaternary oxide layers were fabricated at lower temperatures (280 °C). Compared to conventional IGZO and ternary In-Zn-O (IZO) thin films, VDT IGZO thin film had higher density of the metal-oxide bonds and lower density of the oxygen vacancies. The field-effect mobility of VDT IGZO TFT increased three times with an improved stability under positive bias stress than IZO TFT due to the reduction in oxygen vacancies. Therefore, the VDT process is a simple method that reduces the processing temperature without any additional treatment for quaternary oxide semiconductors with uniform layers.
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We investigated the surface potential (V surf) of exfoliated MoS2 flakes on bare and Au-coated SiO2/Si substrates using Kelvin probe force microscopy. The V surf of MoS2 single layers was larger on ...the Au-coated substrates than on the bare substrates; our theoretical calculations indicate that this may be caused by the formation of a larger electric dipole at the MoS2/Au interface leading to a modified band alignment. V surf decreased as the thickness of the flakes increased until reaching the bulk value at a thickness of ∼20 nm (∼30 layers) on the bare and ∼80 nm (∼120 layers) on the Au-coated substrates, respectively. This thickness dependence of V surf was attributed to electrostatic screening in the MoS2 layers. Thus, a difference in the thickness at which the bulk V surf appeared suggests that the underlying substrate has an effect on the electric-field screening length of the MoS2 flakes. This work provides important insights to help understand and control the electrical properties of metal/MoS2 contacts.
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