The facile synthesis of silicon nanotubes using a surface sol–gel reaction on pyridine nanowire templates is reported and their performance for energy storage is investigated. Organic–inorganic ...hybrid pyridine/silica core‐shell nanowires prepared using surface sol–gel reaction were converted to silica nanotubes by pyrolysis in air; this was followed by the reduction to silicon nanotubes via magnesiothermic reaction. The electrochemical activity of the obtained silicon nanotubes showed excellent cycle stability, suggesting that the hollow one‐dimensional structure would be a good candidate for a high‐capacity anode for a lithium ion battery.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Anaplastic thyroid cancer (ATC) and advanced differentiated thyroid cancers (DTCs) show fatal outcomes, unlike DTCs. Here, we demonstrate mutational landscape of 27 ATCs and 86 advanced DTCs by ...massively-parallel DNA sequencing, and transcriptome of 13 ATCs and 12 advanced DTCs were profiled by RNA sequencing. TERT, AKT1, PIK3CA, and EIF1AX were frequently co-mutated with driver genes (BRAF
and RAS) in advanced DTCs as well as ATC, but tumor suppressors (e.g., TP53 and CDKN2A) were predominantly altered in ATC. CDKN2A loss was significantly associated with poor disease-specific survival in patients with ATC or advanced DTCs, and up-regulation of CD274 (PD-L1) and PDCD1LG2 (PD-L2). Transcriptome analysis revealed a fourth molecular subtype of thyroid cancer (TC), ATC-like, which hardly reflects the molecular signatures in DTC. Furthermore, the activation of JAK-STAT signaling pathway could be a potential druggable target in RAS-positive ATC. Our findings provide insights for precision medicine in patients with advanced TCs.
Follicular thyroid carcinoma (FTC) and benign follicular adenoma (FA) are indistinguishable by preoperative diagnosis due to their similar histological features. Here we report the first RNA ...sequencing study of these tumors, with data for 30 minimally invasive FTCs (miFTCs) and 25 FAs. We also compared 77 classical papillary thyroid carcinomas (cPTCs) and 48 follicular variant of PTCs (FVPTCs) to observe the differences in their molecular properties. Mutations in H/K/NRAS, DICER1, EIF1AX, IDH1, PTEN, SOS1, and SPOP were identified in miFTC or FA. We identified a low frequency of fusion genes in miFTC (only one, PAX8-PPARG), but a high frequency of that in PTC (17.60%). The frequencies of BRAFV600E and H/K/NRAS mutations were substantially different in miFTC and cPTC, and those of FVPTC were intermediate between miFTC and cPTC. Gene expression analysis demonstrated three molecular subtypes regardless of their histological features, including Non-BRAF-Non-RAS (NBNR), as well as BRAF-like and RAS-like. The novel molecular subtype, NBNR, was associated with DICER1, EIF1AX, IDH1, PTEN, SOS1, SPOP, and PAX8-PPARG. The transcriptome of miFTC or encapsulated FVPTC was indistinguishable from that of FA, providing a molecular explanation for the similarly indolent behavior of these tumors. We identified upregulation of genes that are related to mitochondrial biogenesis including ESRRA and PPARGC1A in oncocytic follicular thyroid neoplasm. Arm-level copy number variations were correlated to histological and molecular characteristics. These results expanded the current molecular understanding of thyroid cancer and may lead to new diagnostic and therapeutic approaches to the disease.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Abstract
Highly conducting nanomaterials have garnered significant attention owing to their potential application in Li‐ion batteries for stable electrodes. However, concerns persist regarding their ...dispersion and effective hybridization with active materials. This study reports a novel approach to enhance Si‐based anode materials using less defective graphene oxide (C‐GO) and highly oxidized single‐walled carbon nanotubes (C‐SWCNTs) fabricated using chlorate‐based oxidation. The method involves encapsulating Si alloy (SiA) particles with C‐GO and C‐SWCNTs, eliminating the need for additional additives. Composite structures with lithiophilic N‐doped SWCNTs and highly crystalline reduced C‐GO coatings on SiA surfaces are created through spray drying and subsequent chemical reduction. This unique combination yields high capacities, stable retention behaviors, and remarkable initial capacities (1224 mAh g
−1
) with excellent retention rates (82.3% at 100 cycles, 0.1 C). A LIB full‐cell with a SiA/nanocarbon anode exhibited a high energy density of 350 Wh kg
−1
, while maintaining 65% capacity retention after 200 cycles. The findings demonstrate the potential of this hybrid approach, which eliminates the need for other conducting additives while maintaining a minimal binder content (5 wt.%). This study presents a promising approach for enhancing Si‐based anode materials in lithium‐ion batteries, addressing the dispersion and hybridization challenges in nanomaterial‐enabled electrode design.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
The use of big data, artificial intelligence, and new information and communication technologies has led to sustainable developments and improved business competitiveness. Until recently cloud ...services were classified as having special system requirements for a business organization, and was represented by different cloud computing architecture layers like infrastructure, platform, or software as a service. However, as the environment of IT services undergoes successive changes, companies have been required to reconsider their business models and consider adopting a cloud computing system, which can bring on business achievements and development. Regarding a decision-making model for adopting a cloud computing system, this paper analyzes critical variables in a hierarchical structure of decision areas: technology, organization, and environment, as well as seven factors and 23 attributes based on underlying decision factors of cloud computing adoption by AHP (Analytic Hierarchy Process) and Delphi analysis. Furthermore, this research explores a comparative analysis between demanders and providers of cloud computing adoption. Resultantly, this study suggests several important factors for adopting a cloud computing system: top management support, competitive pressure, and compatibility. From the demander side, the high priority factor was compatibility and competitive pressure; in contrast, related advantage and top management support were regarded as priority factors for providers to service their cloud computing systems.
Na/FeSx batteries have remarkable potential applicability due to their high theoretical capacity and cost‐effectiveness. However, realization of high power‐capability and long‐term cyclability ...remains a major challenge. Herein, ultrafine Fe7S8@C nanocrystals (NCs) as a promising anode material for a Na–ion battery that addresses the above two issues simultaneously is reported. An Fe7S8 core with quantum size (≈10 nm) overcomes the kinetic and thermodynamic constraints of the Na‐S conversion reaction. In addition, the high degree of interconnection through carbon shells improves the electronic transport along the structure. As a result, the Fe7S8@C NCs electrode achieves excellent power capability of 550 mA h g−1 (≈79% retention of its theoretical capacity) at a current rate of 2700 mA g−1. Furthermore, a conformal carbon shell acts as a buffer layer to prevent severe volume change, which provides outstanding cyclability of ≈447 mA h g−1 after 1000 cycles (≈71% retention of the initial charge capacity).
A new approach to directly synthesize extremely small core–shell Fe7S8@C nanocrystals is introduced for Na–ion batteries. The ultrafine Fe7S8 core (≈10 nm) enables a highly reversible conversion reaction and the uniform carbon shell (≈2 nm) enhances the electrical conductivity, leading to outstanding energy density (≈911 Wh kg−1), and excellent rate capability (≈550 mA h g−1 at a current rate of 2700 mA g−1).
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
The contributions of various PM2.5 emission sources to ambient PM2.5 levels during 2013 in the main hub port city (Busan, South Korea) of East Asia was quantified using several receptor modeling ...techniques. Three receptor models of principal component analysis/absolute principal component score (PCA/APCS), positive matrix factorization (PMF), and chemical mass balance (CMB) were used to apportion the source of PM2.5 obtained from the target city. The results of the receptor models indicated that the secondary formation of PM2.5 was the dominant (45–60%) contributor to PM2.5 levels in the port city of Busan. The PMF and PCA/APCS suggested that ship emission was a non-negligible contributor of PM2.5 (up to about 10%) in the study area, whereas it was a negligible contributor based on CMB. The magnitude of source contribution estimates to PM2.5 levels differed significantly among these three models due to their limitations (e.g., PM2.5 emission source profiles and restrictions of the models). Potential source contribution function and concentration-weighted trajectory analyses indicated that long-range transport from sources in the eastern China and Yellow Sea contributed significantly to the level of PM2.5 in Busan.
•The magnitude of source contribution estimates to PM2.5 levels differed significantly among three receptor models.•Analysis of PM2.5 source apportionment by PMF is likely to be more reliable than that by CMB.•The secondary aerosol was a dominant contributor to PM2.5 levels.•The PMF and PCA/APCS suggested that ship emission was a non-negligible contributor of PM2.5.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Flexible energy‐storage devices have attracted growing attention with the fast development of bendable electronic systems. However, it still remains a challenge to find reliable electrode materials ...with both high mechanical flexibility/toughness and excellent electron and lithium‐ion conductivity. This paper reports the fabrication and characterization of highly porous, stretchable, and conductive polymer nanocomposites embedded with carbon nanotubes (CNTs) for application in flexible lithium‐ion batteries. The systematic optimization of the porous morphology is performed by controllably inducing the phase separation of polymethylmethacrylate (PMMA) in polydimethylsiloxane (PDMS) and removing PMMA, in order to generate well‐controlled pore networks. It is demonstrated that the porous CNT‐embedded PDMS nanocomposites are capable of good electrochemical performance with mechanical flexibility, suggesting these nanocomposites could be outstanding anode candidates for use in flexible lithium‐ion batteries. The optimization of the pore size and the volume fraction provides higher capacity by nearly seven‐fold compared to a nonporous nanocomposite.
Highly porous and stretchable polymer–carbon nanotube composites are fabricated for application in flexible lithium‐ion batteries. Because the electrolytes cannot effectively penetrate into the polydimethylsiloxane‐based nanocomposites, interconnected pores are artificially formed by inducing controlled phase separation. The optimization of the pore size and the volume fraction provides higher capacity by nearly seven‐fold compared to a nonporous nanocomposite.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
The power capability of the NASICON‐type Li3V2(PO4)3 electrode is greatly improved by coating with PEDOT, that is, poly(3,4‐ethylenedioxythiophene), a conducting polymer. The Li3V2(PO4)3/PEDOT ...electrode delivers more than 90% of its theoretical capacity (133 mAh g−1) at a 10 C rate and 97% of this capacity is retained at this rate after 100 cycles. This remarkable power and cycle stability achieved by a simple coating process makes this 4 V‐class electrode one of the most promising electrode candidates for next‐generation batteries.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
High-performance cathode materials for K-ion batteries require large K+ diffusion pathways and numerous K+ sites in the stable crystal structure. Herein, we investigate K1.5VOPO4F0.5 composed of ...three-dimensionally interconnected V2O10F bi-octahedra and PO4 tetrahedra as a promising cathode material for K-ion batteries using a combined computational and experimental approach. First-principles calculation results reveal that K+ ions can be facilely diffused along large two-dimensional pathways in the K1.5VOPO4F0.5 structure and that numerous K+ ions can be reversibly de/intercalated in the available voltage range, demonstrating the potential of K1.5VOPO4F0.5 to deliver outstanding electrochemical performance in a K-ion battery system. At a current rate of C/20 (1C = 116 mA g−1), the specific capacity of K1.5VOPO4F0.5 is retained up to ∼116 mA h g−1 with a high average operation voltage of ∼3.8 V (vs. K+/K), corresponding to reversible de/intercalation of ∼1 mol K+ in the structure. Even at 5C, K1.5VOPO4F0.5 delivers ∼79% of the capacity measured at C/20, indicating its excellent power-capability despite the large ionic size of K+. Moreover, K1.5VOPO4F0.5 delivers excellent cycle performance, with ∼86% retention of the initial capacity after 300 cycles at 1C and a high coulombic efficiency of over 99%. Combined studies using ex situ XANES analyses and first-principles calculation indicate occurrence of V4+/V5+ redox reaction of K1.5VOPO4F0.5 for its high operation voltage. We believe that our findings will provide highly useful guidance for the discovery of high-performance electrode materials for rechargeable batteries.
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