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A nitrobenzoxadiazole (NBD)‐based colorimetric chemosensor CNA (N,N,N‐trimethyl‐2‐(2‐(7‐nitrobenzo[c][1,2,5]oxadiazol‐4‐yl)hydrazineyl)‐2‐oxoethan‐1‐aminium chloride) was synthesised. The sensor CNA can detect hypochlorite (ClO−) via colour variation of yellow to colourless. The detection limit for ClO− by CNA was analysed to be 0.36 μM. Moreover, the naked‐eye test strip was successfully applied for ClO− detection. The probing mechanism of CNA to ClO− was proposed to be a hydrolytic cleavage reaction of CNA by ClO− and was demonstrated by electrospray ionisation mass spectrometry (ESI‐MS), Fourier‐transform infrared (FTIR), proton nuclear magnetic resonance (1H NMR) analysis and density functional theory (DFT) calculations. [ABSTRACT FROM AUTHOR]

The conserved THO/TREX (transcription/export) complex is critical for pre-mRNA processing and mRNA nuclear export. In metazoa, TREX is loaded on nascent RNA transcribed by RNA polymerase II in a splicing-dependent fashion; however, how TREX functions is poorly understood. Here we show that Thoc5 and other TREX components are essential for the biogenesis of piRNA, a distinct class of small noncoding RNAs that control expression of transposable elements (TEs) in the Drosophila germline. Mutations in TREX lead to defects in piRNA biogenesis, resulting in derepression of multiple TE families, gametogenesis defects, and sterility. TREX components are enriched on piRNA precursors transcribed from dual-strand piRNA clusters and colocalize in distinct nuclear foci that overlap with sites of piRNA transcription. The localization of TREX in nuclear foci and its loading on piRNA precursor transcripts depend on Cutoff, a protein associated with chromatin of piRNA clusters. Finally, we show that TREX is required for accumulation of nascent piRNA precursors. Our study reveals a novel splicing-independent mechanism for TREX loading on nascent RNA and its importance in piRNA biogenesis.

A fluorometric and colorimetric chemosensor DiPP ((E)-3-(4-(diphenylamino)phenyl)-1-(pyridin-2-yl)prop-2-en-1-one) based on chalcone structure with a triphenylamine group was synthesized. Sensor DiPP detected Pd2+ with fluorescence turn-off and via colorimetry variation of yellow to purple. The binding ratio of DiPP to Pd2+ turned out to be 1 : 1. Detection limits for Pd2+ by DiPP were analyzed to be 0.67 µM and 0.80 µM through the fluorescent and colorimetric methods. Additionally, the fluorescent and colorimetric test strips were applied for probing Pd2+ and displayed that DiPP could obviously discriminate Pd2+ from other metals. The binding feature of DiPP to Pd2+ was presented by ESI-mass, Job plot, NMR titration, ESI-mass, and DFT calculations. [ABSTRACT FROM AUTHOR]

A new thiosemicarbazide-naphthalene-based fluorescent chemosensor FNC ((2-(furan-2-carbonyl)-N-(naphthalen-1-yl)hydrazine-1-carbothioamide)) for Zn2+ was synthesized and identified. FNC was applied to selectively detect Zn2+ with fluorescent turn-on response. The detection limit was determined to be 1.93 µM, which is much below the WHO standard (76.5 µM). The detecting mechanism of FNC to Zn2+ was revealed to bind FNC to Zn2+ in the proportion of 1: 1 by Job plot, ESI-mass and 1H NMR titrations. DFT and TD-DFT calculations were performed for FNC and FNC-Zn2+, which provide insight into structural, electronic and photophysical properties. [ABSTRACT FROM AUTHOR]

A new nitrobenzoxadiazole (NBD)‐based chemosensor N′‐(7‐nitrobenzo[c][1,2,5]oxadiazol‐4‐yl)thiophene‐2‐carbohydrazide (NTCH) was synthesized for detecting Hg2+. NTCH could sense Hg2+ through a color change method from pale yellow to pink. Binding ratio of NTCH and Hg2+ was determined to be 1:1 with the analysis of electrospray ionization mass spectrometry and Job plot. Detection limit turned out to be 0.69 μM. In addition, NTCH could be successfully utilized for detecting Hg2+ in real water samples and visible color test strips. The probing mechanism of NTCH to Hg2+ was explained with 1H nuclear magnetic resonance (NMR) titration, Job plot, electrospray ionization mass spectrometry (ESI‐MS), and theoretical calculations. [ABSTRACT FROM AUTHOR]

A dinitrophenol-based colorimetric chemosensor sequentially sensing Cu2+ and S2−, HDHT ((E)-2-(2-(2-hydroxy-3,5-dinitrobenzylidene)hydrazineyl)-N,N,N-trimethyl-2-oxoethan-1-aminium), was designed and synthesized. The HDHT selectively detected Cu2+ through a color change of yellow to colorless. The calculated detection limit of the HDHT for Cu2+ was 6.4 × 10−2 μM. In the interference test, the HDHT was not considerably inhibited by various metal ions in its detection of Cu2+. The chelation ratio of the HDHT to Cu2+ was determined as 1:1 by using a Job plot and ESI-MS experiment. In addition, the HDHT–Cu2+ complex showed that its color selectively returned to yellow only in the presence of S2−. The detection limit of the HDHT–Cu2+ complex for S2− was calculated to be 1.2 × 10−1 μM. In the inhibition experiment for S2−, the HDHT–Cu2+ complex did not significantly interfere with other anions. In the real water-sample test, the detection performance of the HDHT for Cu2+ and S2− was successfully examined. The detection features of HDHT for Cu2+ and the HDHT–Cu2+ for S2− were suggested by the Job plot, UV–Vis, ESI-MS, FT-IR spectroscopy, and DFT calculations. [ABSTRACT FROM AUTHOR]

A naphthol and nitro‐aniline‐based fluorometric and colorimetric chemosensor BHMN, 1,1‐bis(2‐(((E)‐(2‐hydroxy naphthalene‐1‐yl)methylene)amino)ethyl)‐3‐(4‐nitrophenyl)thiourea, was synthesized. Sensor BHMN detected Al3+ with fluorescence turn‐on and Fe3+ via color variation of colorless to purple. Binding ratios of BHMN to Al3+ and Fe3+ turned out to be 1 : 1. Detection limits for Al3+ and Fe3+ by BHMN were analyzed to be 8.22 μM and 3.10 μM. Additionally, the naked‐eye test strip was applied for sensing Fe3+ and showed that BHMN could effectively discriminate Fe3+ from Fe2+ and other cations. The binding mechanisms of BHMN to Al3+ and Fe3+ were identified by ESI‐mass, Job plot, NMR titration, and DFT calculations. [ABSTRACT FROM AUTHOR]

A naphthol and nitro‐aniline‐based fluorometric and colorimetric chemosensor BHMN, 1,1‐bis(2‐(((E)‐(2‐hydroxy naphthalene‐1‐yl)methylene)amino)ethyl)‐3‐(4‐nitrophenyl)thiourea, was synthesized. Sensor BHMN detected Al3+ with fluorescence turn‐on and Fe3+ via color variation of colorless to purple. Binding ratios of BHMN to Al3+ and Fe3+ turned out to be 1 : 1. Detection limits for Al3+ and Fe3+ by BHMN were analyzed to be 8.22 μM and 3.10 μM. Additionally, the naked‐eye test strip was applied for sensing Fe3+ and showed that BHMN could effectively discriminate Fe3+ from Fe2+ and other cations. The binding mechanisms of BHMN to Al3+ and Fe3+ were identified by ESI‐mass, Job plot, NMR titration, and DFT calculations. [ABSTRACT FROM AUTHOR]

Among many candidates for photoanode materials of photoelectrochemical (PEC) cell, nanostructured tungsten trioxide (WO3) is regarded as one of the most promising materials due to its superior electrical properties and adequate bandgap (∼2.8 eV) and band edge position. WO3 nanoflakes (WO3 NFs), which have merits on its high surface area and crystallinity, have been actively studied for this manner but solar-to-hydrogen efficiency of WO3 NFs based photoanode is still not sufficient both in light absorption and charge separation. Plasmon-induced enhancement using Au nanoparticles is excellent approach for both the efficiency of light absorption and charge separation of WO3. However, it still needs optimization on its amount, shape, coverage, and etc. Here, we synthesized WO3 NFs by solvothermal growth and decorated gold nanoparticles on these nanoflakes by e-beam evaporation and rapid thermal annealing process in a row. By this process, a large-area AuNPs/WO3 nanocomposite structure with various size, interparticle distance, and coverage of AuNPs were fabricated. These AuNPs/WO3 NFs type photoanode achieve high light absorption both in UV and visible range and consequently higher photocurrent density. The optimized AuNPs/WO3 nanocomposite photoanode exhibits 1.01 mA cm−2 of photocurrent density, which is increased to 19.8% compared with bare WO3 nanoflakes. Field emission-scanning electron microscope, x-ray diffraction, UV–vis spectrometer analysis were measured to analyze the morphology and crystallinity and relationship between structure and PEC performance. [ABSTRACT FROM AUTHOR]

In this paper, we propose a method to increase the coupling between the ground and the antenna to improve the radiation performance of the mobile antenna. By adjusting the length of the slot antenna located at the center of the 48 mm × 15 mm ground resonating at 2.45 GHz, the coupling between the ground and the antenna can be controlled. When the coupling between the ground and the antenna is sufficiently strong, the ground resonance mode is strongly excited and a better radiation performance can be obtained. As the length of the slot antenna increases from 5 to 10 mm, the coupling between the ground and the antenna becomes stronger and the impedance bandwidth of −10 dB at 2.45 GHz becomes five times wider from 160 MHz (6.5%) to 780 MHz (31.8%). [ABSTRACT FROM AUTHOR]