Embedding cubane M4(OH)4 (M=Ni, Co) clusters within the matrix of metal–organic frameworks (MOFs) is a strategy to develop materials with unprecedented synergistic properties. Herein, a new material ...type based on the pore‐space partition of the cubic primitive minimal‐surface net (MOF‐14‐type) has been realized. CTGU‐15 made from the Ni4(OH)4 cluster not only has very high BET surface area (3537 m2 g−1), but also exhibits bi‐microporous features with well‐defined micropores at 0.86 nm and 1.51 nm. Furthermore, CTGU‐15 is stable even under high pH (0.1 m KOH), making it well suited for methanol oxidation in basic medium. The optimal hybrid catalyst KB&CTGU‐15 (1:2) made from ketjen black (KB) and CTGU‐15 exhibits an outstanding performance with a high mass specific peak current of 527 mA mg−1 and excellent peak current density (29.8 mA cm−2) at low potential (0.6 V). The isostructural cobalt structure (CTGU‐16) has also been synthesized, further expanding the application potential of this material type.
Split pores: A new 3D microporous metal–organic framework containing cubane Ni4(OH)4 clusters can serve as an electrocatalyst for the methanol oxidation reaction (MOR). The optimal hybrid material shows impressive electrocatalytic performance including a high mass specific peak current of 527 mA mg−1 and excellent peak current density (29.8 mA cm−2) at a very low potential (0.6 V).
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Grain weight (GW) is one of the component traits of wheat yield. Existing reports have shown that multiple phytohormones are involved in the regulation of GW in different crops. However, the ...potential role of jasmonic acid (JA) remains unclear. Here, we report that triticale grain weight 1 (tgw1) mutant, with marked reductions in both GW and JA content, is caused by a premature stop mutation in keto-acyl thiolase 2B (KAT-2B) involved in β-oxidation during JA synthesis. KAT-2B overexpression increases GW in wild type and boosts yield. Additionally, KAT-2B compliments the grain defect in tgw1 and rescues the lethal phenotype of the Arabidopsis kat2 mutant in a sucrose-free medium. Despite the suppression of JA synthesis in tgw1 mutant, ABA synthesis is upregulated, which is accompanied by enhanced expression of SAG3 and reduction of chlorophyll content in leaves. Together, these results demonstrate a role of the JA synthetic gene KAT-2B in controlling GW and its potential application value for wheat improvement.
In the past two decades, reversible data hiding (RDH), also referred to as lossless or invertible data hiding, has gradually become a very active research area in the field of data hiding. This has ...been verified by more and more papers on increasingly wide-spread subjects in the field of RDH research that have been published these days. In this paper, the various RDH algorithms and researches have been classified into the following six categories: 1) RDH into image spatial domain; 2) RDH into image compressed domain (e.g., JPEG); 3) RDH suitable for image semi-fragile authentication; 4) RDH with image contrast enhancement; 5) RDH into encrypted images, which is expected to have wide application in the cloud computation; and 6) RDH into video and into audio. For each of these six categories, the history of technical developments, the current state of the arts, and the possible future researches are presented and discussed. It is expected that the RDH technology and its applications in the real word will continue to move ahead.
Polyanion‐type sodium (Na) vanadium phosphate in the form of Na3V2(PO4)3 has demonstrated reasonably high capacity, good rate capability, and excellent cyclability. Two of three Na ions per formula ...can be deintercalated at a potential 3.4 V versus Na+/Na with oxidation of V3+/4+. In the reversible process, two Na ions intercalate back resulting in a discharge capacity of 117.6 mAh g−1. Further intercalation is possible but at a low potential of 1.4 V versus Na+/Na accompanied by vanadium reduction V3+/2+, leading to a capacity of 60 mAh g−1. Due to its marvelous electrochemical performance, it has attracted a lot of attention since its discovery in the 1990s. To develop truly useable polyanion‐type vanadium phosphate, better understanding of its crystal configuration, sodium ions' transportation, and electronic structure is essential. Therefore, this review only focuses on the inside of crystal configuration and electronic structure of polyanion‐type vanadium phosphate, Na3V2(PO4)3, since there are a few good reviews on various processing technologies.
Polyanion sodium vanadium phosphate has been recognized as a potential cathode material for the next generation of sodium‐ion batteries. This article provides a detailed review on the crystallography structure, electronic structure, sodium ion transportation pathway, and intercalation/deintercalation mechanisms. The review also provides different strategies and methodologies to stabilize structure, increase specific energy, and enhance electronic and ionic conductivity.
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Non‐metal‐based single‐atom catalysts (SACs) offer low cost, simple synthesis methods, and effective regulation for substrates. Herein, we developed a simplified pressurized gas‐assisted process, and ...report the first non‐metal single‐atom phosphorus with atomic‐level dispersion on unique single‐crystal Mo2C hexagonal nanosheet arrays with a (001) plane supported by carbon sheet (SAP‐Mo2C‐CS). The SAP‐Mo2C‐CS is structurally stable and shows exceptional electrocatalytic activity for the hydrogen evolution reaction (HER). A so‐called high‐active “window” based on the active sites of P atoms and their adjacent Mo atoms gives a ΔGH* close to zero for hydrogen evolution, which is the most ideal ΔGH* reported so far. Meanwhile, the moderate d‐band center value of SAP‐Mo2C‐CS can be also used as an ideal standard value to evaluate the HER performance in non‐metal‐based SACs.
A simplified pressurized gas‐assisted process, provides the first non‐metal single‐atom phosphorus with atomic‐level dispersion on unique single‐crystal Mo2C hexagonal nanosheet arrays supported by a carbon sheet. This single‐atom catalyst system is structurally stable and has exceptional electrocatalytic activity for the hydrogen evolution reaction (HER).
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Background/Aims
Traumatic dental injuries (TDIs) are considered to be a public dental health problem worldwide. The aim of the current study was to provide the worldwide tendency and perspectives in ...TDIs in the last two decades via bibliometric analysis.
Methods
‘‘Tooth injuries’’ was searched as the Medical Subject Headings term within PubMed with the date range from 1999 to 2018. Two investigators perused information in the articles according to the inclusion and exclusion criteria. The articles were independently categorized according to the following aspects: (a) annual scholarly output; (b) leading countries or regions; (c) leading journals; (d) productive authors; (e) citations; (f) study design; (f) distribution of topics; and (g) the type of dentition and TDIs. VOSviewer 1.6.7 and Citespace 5.2 were used for analyzing and visualizing bibliometric networks.
Results
A total of 2627 articles about traumatic dental injuries were published and indexed in PubMed during the two decades, and the number of publications on traumatic dental injuries was rising in general. The research outputs were mainly concentrated in developed countries and affiliated hospitals of universities. Brazil was the most productive country. The journal Dental Traumatology had the most contributions to the scientific research of traumatic dental injuries. “Case report” was the most frequent type of article (36.50%), followed by cross‐sectional studies (19.57%) and case‐control studies (13.67%). Most studies focused on the treatment of TDIs (38.94%), especially for avulsion (21.01%), crown fracture (9.71%), and intrusion (5.25%). Permanent teeth (66%) were the dominant dentition.
Conclusion
There is a lack of high‐quality well‐designed studies such as cohort studies. The number of publications on prevention and the primary dentition is disproportionate in relation to their significance.
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BFBNIB, CMK, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
The p-GaN gate-based gallium nitride (GaN) power devices are a promising technology for power electronics applications. However, these devices suffer from dynamic on-resistance (R ds, on ) and gate ...threshold voltage (V th ) shifts during operation. The dynamic R ds, on is typically evaluated in a switching circuit, whereas the V th shift is measured using a curve tracer. Both parameter evaluations require distinct setups and do not represent the same operating conditions. To overcome these drawbacks, this letter proposes a circuit capable of measuring both parameters in a hard-switching operation under the same operating conditions. Using this circuit, an EPC2014 C device is characterized, and both parameters are reported.
Controlling the solution‐state aggregation of conjugated polymers for producing specific microstructures remains challenging. Herein, a practical approach is developed to finely tune the solid‐state ...microstructures through temperature‐controlled solution‐state aggregation and polymer crystallization. High temperature generates significant conformation fluctuation of conjugated backbones in solution, which facilitates the polymer crystallization from solvated aggregates to orderly packed structures. The polymer films deposited at high temperatures exhibit less structural disorders and higher electron mobilities (up to two orders of magnitude) in field‐effect transistors, compared to those deposited at low temperatures. This work provides an effective strategy to tune the solution‐state aggregation to reveal the relationship between solution‐state aggregation and solid‐state microstructures of conjugated polymers.
Using temperature‐controlled polymer aggregation, the solid‐state microstructures of conjugated polymers are finely tuned. The temperature‐controlled strategy enhances the molecular ordering in thin films and leads to efficient charge transport. A polymer transistor with tuned molecular ordering exhibited improved electron mobilities of up to 3.71 cm2 V−1 s−1, which is two orders of magnitude higher than the disordered samples.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Abstract
Conventional chemotherapy remains the primary treatment option for triple-negative breast cancer (TNBC). However, the current chemotherapeutic drugs have limited effects on TNBC, and often ...lead to serious side effects as well as drug resistance. Thus, more effective therapeutic options are sorely needed. As c-MYC oncogene is highly expressed during TNBC pathogenesis, inhibiting c-MYC expression would be an alternative anti-TNBC strategy. In this study, we designed and synthesized a serial of quinoxaline analogs that target c-MYC promoter G-quadruplex (G4), which is believed to be a repressor of c-MYC transcription. Among them, a difluoro-substituted quinoxaline QN-1 was identified as the most promising G4-stabilizing ligand with high selectivity to c-MYC G4 over other G4s, which is distinguished from many other reported ligands. Intracellular studies indicated that QN-1 induced cell cycle arrest and apoptosis, repressed metastasis and inhibited TNBC cell growth, primarily due to the downregulation of c-MYC transcription by a G4-dependent mechanism. Notably, inhibition by QN-1 was significantly greater for c-MYC than other G4-driven genes. Cancer cells with c-MYC overexpression were more sensitive to QN-1, relative to normal cells. Furthermore, QN-1 effectively suppressed tumor growth in a TNBC mouse model. Accordingly, this work provides an alternative strategy for treating TNBC.
Display omitted Chan–Lam coupling reactions and their applications on the synthesis of a number of differently functionalized heterocycles are reviewed. This report contains 125 references.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP