Differentiation of Superoxide Radical Anion and Singlet Oxygen and Their Concurrent Quantifications by Nuclear Magnetic Resonance.

While there have been various techniques, assays, and commercial kits developed to measure reactive oxygen species (ROS) with varying degrees of success, there is a lack of innovative methods to differentiate and quantify them simultaneously. In this work, we demonstrate a 19F nuclear magnetic resonance (NMR)-based method to differentiate two important types of ROS, superoxide radical anion and singlet oxygen, and to quantify them concurrently. By taking advantage of the unique chemical reactivity of two fluorine-containing molecules, 4-fluoro-3-methylphenyl boronic acid and 4-fluoro-3-methylphenol, serving as 19F NMR probes, we are able to differentiate and quantify, for the first time, superoxide radical anion and singlet oxygen generated by photosensitizers (PSs) concurrently. The results reveal that relative amounts of superoxide radical anion and singlet oxygen generated by a PS under light illumination are oftentimes sensitive to the environment, such as the presence or absence of electron donors. This method provides a means to identify the type of mechanism by which a PS functions under a given condition. We envision that this relatively simple, yet robust, method would be beneficial to a broad range of ROS-pertinent studies, such as photodynamic therapy and photoredox reactions.

Parallelized Particle Swarm Optimization on FPGA for Realtime Ballistic Target Tracking.

This paper addresses the problem of tracking a high-speed ballistic target in real time. Particle swarm optimization (PSO) can be a solution to overcome the motion of the ballistic target and the nonlinearity of the measurement model. However, in general, particle swarm optimization requires a great deal of computation time, so it is difficult to apply to realtime systems. In this paper, we propose a parallelized particle swarm optimization technique using field-programmable gate array (FPGA) to be accelerated for realtime ballistic target tracking. The realtime performance of the proposed method has been tested and analyzed on a well-known heterogeneous processing system with a field-programmable gate array. The proposed parallelized particle swarm optimization was successfully conducted on the heterogeneous processing system and produced similar tracking results. Also, compared to conventional particle swarm optimization, which is based on the only central processing unit, the computation time is significantly reduced by up to 3.89×.

Introducing MdTFL1 Promotes Heading Date and Produces Semi-Draft Phenotype in Rice.

Flowering time (in rice, termed the heading date), plant height, and grain number are crucial agronomic traits for rice productivity. The heading date is controlled via environmental factors (day length and temperature) and genetic factors (floral genes). TERMINAL FLOWER 1 (TFL1) encodes a protein that controls meristem identity and participates in regulating flowering. In this study, a transgenic approach was used to promote the heading date in rice. We isolated and cloned apple MdTFL1 for early flowering in rice. Transgenic rice plants with antisense MdTFL1 showed an early heading date compared with wild-type plants. A gene expression analysis suggested that introducing MdTFL1 upregulated multiple endogenous floral meristem identity genes, including the (early) heading date gene family FLOWERING LOCUS T and MADS-box transcription factors, thereby shortening vegetable development. Antisense MdTFL1 also produced a wide range of phenotypic changes, including a change in overall plant organelles that affected an array of traits, especially grain productivity. The transgenic rice exhibited a semi-draft phenotype, increased leaf inclination angle, restricted flag leaf length, reduced spikelet fertility, and fewer grains per panicle. MdTFL1 plays a central role in regulating flowering and in various physiological aspects. These findings emphasize the role of TFL1 in regulating flowering in shortened breeding and expanding its function to produce plants with semi-draft phenotypes.

The Synergistic Effects of Environmental and Genetic Factors on the Regulation of Anthocyanin Accumulation in Plant Tissues.

Anthocyanin accumulation is responsible for the coloration of apple fruit, and their accumulation depends on the expression of anthocyanin biosynthesis-related genes. Light is an environmental stimulus that induces fruit color by regulating genes involved in the anthocyanin biosynthesis pathway. In this study, the roles of light and genetic factors on fruit coloration and anthocyanin accumulation in apple fruit were investigated. Three genes in the anthocyanin biosynthesis pathway, MdCHS, MdANS, and MdUFGT1, were synthesized and cloned into a viral-based expression vector system for transient expression in 'Ruby S' apple fruits. Apple fruits were agroinfiltrated with expression vectors harboring MdCHS, MdANS, and MdUFGT1. Agroinfiltrated apple fruits were then either kept in the dark (bagged fruits) or exposed to light (exposed fruits). The agroinfiltrated fruits showed significantly different coloration patterns, transcript expression levels, and anthocyanin accumulation compared to the control fruits. Moreover, these parameters were higher in exposed fruits than in bagged fruits. For stable expression, MdCHS was introduced into a binary vector under the control of the rice α-amylase 3D (RAmy3D) promoter. The ectopic overexpression of MdCHS in transgenic rice calli showed a high accumulation of anthocyanin content. Taken together, our findings suggest that light, together with the overexpression of anthocyanin biosynthesis genes, induced the coloration and accumulation of anthocyanin content in apple fruits by upregulating the expression of the genes involved in the anthocyanin biosynthesis pathway.

Fabrication of nonenzymatic electrochemical sensor based on Zn@ZnO core-shell structures obtained via pulsed laser ablation for selective determination of hydroquinone.

Herein, we fabricated a more sensitive nonenzymatic electrochemical sensor for the selective determination of hydroquinone as a targeted pollutant at zinc@zinc oxide (Zn@ZnO) core-shell nanostructures. The nanostructured Zn@ZnO materials were produced using pulsed laser ablation in an aqueous medium without the use of any reducing agents or surfactants. The detailed structural, morphological, elemental composition, and electrochemical voltammetric analyses revealed a significant improvement in Zn@ZnO performance for selective hydroquinone detection. A broad linear calibration response was obtained as 10-90 µM with high sensitivity of 0.5673 µA µM-1 cm-2 and the low detection limit was 0.10443 µM for detection of hydroquinone. The modified Zn@ZnO electrode's excellent electrochemical sensing performance was attributed to the accessibility of a high electrochemically active surface area (EASA = 0.00345 µF/cm2) and an improved electron transfer rate. Stability and antiinterference tests were also carried out. A 100 fold increase in the concentration of common cations and anions (Na+, Mg2+, Cl-, SO42-, and NO3-) did not affect the selective determination of HQ. As a result, the fabricated electrochemical sensor has a wide range of potential applications in environmental and biomedical science.

Architecture of visible-light induced Z-scheme MoS2/g-C3N4/ZnO ternary photocatalysts for malachite green dye degradation.

The synthesis of bilayer heterojunctions has received considerable attention recently. Fabrication of novel bilayer composites is of significant interest to improve their photocatalytic efficiency. In this study, molybdenum disulfide (MoS2), a layered dichalcogenide material exhibiting unique properties, in combination with graphitic carbon nitride (g-C3N4), a carbon-based layered material, was fabricated with small amounts of zinc oxide (ZnO). Three composites, MoS2/g-C3N4, MoS2/ZnO, and MoS2/g-C3N4/ZnO were prepared via a simple exfoliation method and characterized by various physicochemical methods. The Z-scheme charge transfer mechanism in the prepared ternary composite improves efficiency by inhibiting the recombination rate of electron-hole pairs. It has shown excellent performance in degrading a major water contaminant, malachite green (MG) dye, under visible light irradiation.

Versatile Cp*Co(III)(LX) Catalyst System for Selective Intramolecular C-H Amidation Reactions.

Herein, we report the development of a tailored cobalt catalyst system of Cp*Co(III)(LX) toward intramolecular C-H nitrene insertion of azidoformates to afford cyclic carbamates. The cobalt complexes were easy to prepare and bench-stable, thus offering a convenient reaction protocol. The catalytic reactivity was significantly improved by the electronic tuning of the bidentate LX ligands, and the observed regioselectivity was rationalized by the conformational analysis and DFT calculations of the transition states. The superior performance of the newly developed cobalt catalyst system could be broadly applied to both C(sp2)-H and C(sp3)-H carbamation reactions under mild conditions.

Iterative C-H Functionalization Leading to Multiple Amidations of Anilides.

Polyaminobenzenes were synthesized by the ruthenium-catalyzed iterative C-H amidation of anilides using dioxazolones as an amino source. This strategy could be implemented by the sequential activation of C-H bonds of formerly generated compounds by cascade chelation assistance of newly installed amide groups. Computational studies provided a rationale.

Boron-Catalyzed Silylative Reduction of Nitriles in Accessing Primary Amines and Imines.

Silylative reduction of nitriles was studied under transition metal-free conditions by using B(C6F5)3 as a catalyst with hydrosilanes as a reductant. Alkyl and (hetero)aryl nitriles were efficiently converted to primary amines or imines under mild conditions. The choice of silanes was found to determine the selectivity: while a full reduction of nitriles was highly facile, the use of sterically bulky silanes allowed for the partial reduction leading to N-silylimines.

Comparative Catalytic Activity of Group†9 [Cp*M(III)] Complexes: Cobalt-Catalyzed C-H Amidation of Arenes with Dioxazolones as Amidating Reagents.

A procedure for the [Cp*Co(III)]-catalyzed direct C-H amidation of arenes with dioxazolone has been developed. This reaction proceeds under straightforward and mild conditions with a broad range of substrates, including anilides. A comparative study on the catalytic activity of Group 9 [{Cp*MCl2}2] complexes revealed the unique efficiency of the cobalt catalyst.

Chemoselective Silylative Reduction of Conjugated Nitriles under Metal-Free Catalytic Conditions: ß-Silyl Amines and Enamines.

The B(C6F5)3-catalyzed silylative reduction of conjugated nitriles has been developed to afford synthetically valuable ß-silyl amines. The reaction is chemoselective and proceeds under mild conditions. Mechanistic elucidation indicates that it proceeds by rapid double hydrosilylation of the conjugated nitrile to an enamine intermediate which is subsequently reduced to the ß-silyl amine, thus forming a new C(sp(3))-Si bond. Based on this mechanistic understanding, a preparative route to enamines was also established using bulky silanes.

Identification of intracellular activation mechanism of rhamnogalacturonan-I type polysaccharide purified from Panax ginseng leaves in macrophages and roles of component sugar chains on activity.

This study aimed to investigate the mechanisms underlying intracellular signaling pathways in macrophages in relation to the structural features of rhamnogalacturonan (RG) I-type polysaccharide (PGEP-I) purified from Panax ginseng leaves. For this investigation, we used several specific inhibitors and antibodies against mitogen-activated protein kinase (MAPK), nuclear factor-kappa B (NF-κB), and pattern recognition receptors (PRRs). Furthermore, we investigated the roles of component sugar chains on immunostimulating activity through a sequential enzymatic and chemical degradation steps. We found that PGEP-I effectively induced the phosphorylation of several MAPK- and NF-κB-related proteins, such as p38, cJun N-terminal kinase (JNK), extracellular signal-regulated kinase (ERK), and p65. Particularly, immunocytochemistry analysis confirmed the PGEP-I-induced translocation of p65 into the nucleus. Furthermore, the breakdown of PGEP-I side chains and main chain during sequential enzymatic and chemical degradation reduced the PGEP-I-induced macrophage cytokine secretion activity. IL-6, TNF-α, and NO secreted by macrophages are associated with several signaling pathway proteins such as ERK, JNK, and NF-κB and several PRRs such as dectin-1, CD11b, CD14, TLR2, TLR4, and SR. Thus, these findings suggest that PGEP-I exerts potent macrophage-activating effects, which can be attributed to its typical RG-I structure comprising arabinan, type II arabinogalactan, and rhamnose-galacturonic acid repeating units in the main chain.

Laser-Synthesized Ru-Anchored Few-Layer Black Phosphorus for Superior Hydrogen Evolution: Role of Acoustic Levitation.

Electrochemical water splitting, driven by processed catalysts, is the most reasonable method for hydrogen production. This study demonstrates an activation phenomenon with ruthenium (Ru) nanoclusters on few-layered black phosphorus (BP), greatly enhancing the electrocatalytic hydrogen evolution reaction (HER). Efficient BP exfoliation was achieved using acoustic levitators and pulsed laser irradiation in liquids (PLIL), yielding charge-transfer Ru-nanoclusters on modulated surfaces. Various PLIL parameters were examined for the optimal BP sheet size. After ruthenization, Ru's d-band center facilitated hydrogen adsorption via Ru-H bonding. Synergy between BP's charge-carrier properties and Ru's active sites boosted HER kinetics with an ultralow overpotential of 84 mV at 10 mA/cm2 in KOH. Additionally, the RuO2 || RuBP-2 electrolyzer demonstrated remarkable overall water splitting performance at ∼1.60 V at 10 mA/cm2. These results highlight the pivotal role of metal nanoclusters on exfoliated BP surfaces and offer a refined strategy for high-density electrocatalysts in energy conversion.

Immunostimulating effects of ulvan type polysaccharide isolated from Korean Ulva pertusa in cyclophosphamide-induced immunosuppressed BALB/c mice.

This study aimed to determine the immunostimulatory activities of ulvan type polysaccharides isolated from Ulva pertusa. First, U. pertusa polysaccharide (UPP) mainly consists of rhamnose, glucuronic acid, iduronic acid, and xylose, which are typical ulvan type monosaccharides. UPP induced phosphorylation of the mitogen-activated protein kinase and nuclear factor-kappa B pathways in macrophages, subsequently triggering cytokine release and phagocytosis. The effects were closely associated with pattern recognition receptors such as dectin-1, mannose receptor, CD11b, CD14, and Toll-like receptors 2 and 4. Moreover, prophylactic administration of UPP was found to protect against body weight loss and lymphatic organ damage in cyclophosphamide-induced immunosuppressed mice. In addition, UPP demonstrated significant stimulatory effects on various immunocytes, such as T cells, B cells, macrophages, and natural killer cells derived from the spleen. These effects were closely related to the mitogen-activated protein kinase and nuclear factor-kappa B pathways, and significant secretion of immunostimulatory cytokines such as IL-6, -12, and TNF-α was noted in both blood and spleen samples. Impairment of the short-chain fatty acid balance in the cecum was prevented by UPP administration in a dose-dependent manner. Consequently, these results suggest that the UPP isolated from U. pertusa contributes to immune system activation.

Impact of the COVID-19 Pandemic on Adolescent Self-Harm: Based on a National Emergency Department Information System.

Republic of Korea's suicide rate is the highest among Organization for Economic Co-operation and Development countries. In Republic of Korea, suicide is the leading cause of death among young people aged 10-19 years. This study aimed to identify changes in patients aged 10-19 years who visited the emergency department in Republic of Korea after inflicting self-harm over the past five years and to compare the situations before and after the outbreak of the COVID-19 pandemic. Analysis of government data revealed that the average daily visits per 100,000 were 6.25, 8.18, 13.26, 15.31, and 15.71 from 2016 to 2020, respectively. The study formed four groups for further analysis, with the population divided by sex and age (10-14 and 15-19 years old). The late-teenage female group showed the sharpest increase and was the only group that continued to increase. A comparison of the figures 10 months before and after the outbreak of the pandemic revealed a statistically significant increase in self-harm attempts by only the late-teenage female group. Meanwhile, visits (per day) in the male group did not increase, but the rates of death and ICU admission increased. Additional studies and preparations that account for age and sex are warranted.

In situ studies on free-standing synthesis of nanocatalysts via acoustic levitation coupled with pulsed laser irradiation.

Acoustic levitation is a distinctive and versatile tool for levitating and processing free-standing single droplets and particles. Liquid droplets suspended in an acoustic standing wave provide container-free environments for understanding chemical reactions by avoiding boundary effects and solid surfaces. We attempted to use this strategy for the production of well-dispersed uniform catalytic nanomaterials in an ultraclean confined area without the addition of external reducing agents or surfactants. In this study, we report on the synthesis of gold and silver nanoparticles (NPs) via acoustic levitation coupled with pulsed laser irradiation (PLI). In situ UV-Visible and Raman spectroscopic techniques were performed to monitor the formation and growth of gold and silver NPs. The PLI was used for the photoreduction of targeted metal ions present in the levitated droplets to generate metal NPs. Additionally, the cavitation effect and bubble movement accelerate the nucleation and decrease the size of NPs. The synthesized Au NPs with âˆ¼ 5 nm size showed excellent catalytic behavior towards the conversion of 4-nitrophenol to 4-aminophenol. This study may open a new door for synthesizing various functional nanocatalysts and for achieving new chemical reactions in suspended droplets.

In-situ monitoring of thiazine molecular aggregation in various solvents via a free-standing acoustic levitator.

In this work, we explored the in-situ reaction modeling of the molecular self-aggregation of methylene blue (MB), which is a cationic thiazine dye, in different solvents via a container-less acoustic levitator by floating of a single droplet. Our in-situ spectroscopic study revealed that the dimer essentially has a sandwich structural geometry with a deviation from parallel stacking and horizontal arrangements in the molecular planes. The real time conversion of the monomer in MB into a dimer and their dynamics in water and ethanol media were monitored using a free-standing acoustic levitator droplet system. The absorption spectra revealed changes in the two resolved peaks (monomer and dimer) and orderliness when water and ethanol were used as the media. Interestingly, the enhancement in the dimerization of MB could be attributed to droplet evaporation, which is difficult to observe in typical reactor containers. Moreover, acidic protonation resulted in a change in the aggregation orientation direction of the MB molecules, forming an unusual J-aggregation. Theoretical DFT calculations revealed that MB underwent typical H-aggregation and J-aggregation in the different solvent environments, and their orientations well matched the spectroscopic data.

Identification of genes associated with the regulation of cold tolerance and the RNA movement in the grafted apple.

In grafted apple, rootstock-derived signals influence scion cold tolerance by initiating physiological changes to survive over the winter. To understand the underlying molecular interactions between scion and rootstock responsive to cold, we developed transcriptomics and metabolomics data in the stems of two scion/rootstock combinations, 'Gala'/'G202' (cold resistant rootstock) and 'Gala'/'M9' (cold susceptible rootstock). Outer layers of scion and rootstock stem, including vascular tissues, were collected from the field-grown grafted apple during the winter. The clustering of differentially expressed genes (DEGs) and gene ontology enrichment indicated distinct expression dynamics in the two graft combinations, which supports the dependency of scion cold tolerance on the rootstock genotypes. We identified 544 potentially mobile mRNAs of DEGs showing highly-correlated seasonal dynamics between scion and rootstock. The mobility of a subset of 544 mRNAs was validated by translocated genome-wide variants and the measurements of selected RNA mobility in tobacco and Arabidopsis. We detected orthologous genes of potentially mobile mRNAs in Arabidopsis thaliana, which belong to cold regulatory networks with RNA mobility. Together, our study provides a comprehensive insight into gene interactions and signal exchange between scion and rootstock responsive to cold. This will serve for future research to enhance cold tolerance of grafted tree crops.

Fabrication of Ru-CoFe2O4/RGO hierarchical nanostructures for high-performance photoelectrodes to reduce hazards Cr(VI) into Cr(III) coupled with anodic oxidation of phenols.

Dual-functional photo (electro)catalysis (PEC) is a key strategy for removing coexisting heavy metals and phenolic compounds from wastewater treatment systems. To design a PEC cell, it is crucial to use chemically stable and cost-effective bifunctional photocatalysts. The present study shows that ruthenium metallic nanoparticles decorated with CoFe2O4/RGO (Ru-CoFe2O4/RGO) are effective bifunctional photoelectrodes for the reduction of Cr(VI) ions. Ru-CoFe2O4/RGO achieves a maximum Cr(VI) reduction rate of 99% at 30 min under visible light irradiation, which is much higher than previously reported catalysts. Moreover, PEC Cr(VI) reduction rate is also tuned by adding varying concentration of phenol. A mechanism for the concurrent removal of Cr(VI) and phenol has been revealed over a bifunctional Ru-CoFe2O4/RGO catalyst. A number of key conclusions emerged from this study, demonstrating the dual role of phenol during Cr(VI) reduction by PEC. Anodic oxidation of phenol produces the enormous H+ ion, which appears to be a key component of Cr(VI) reduction. Additionally, phenolic molecules serve as hole (h+) scavengers that reduce e-/h+ recombination, thus enhancing the reduction rate of Cr(VI). Therefore, the Ru-CoFe2O4/RGO photoelectrode exhibits a promising capability of reducing both heavy metals and phenolic compounds simultaneously in wastewater.