Search

This paper addresses the problem of real-time onboard routing for dynamic low earth orbit (LEO) satellite networks. It is difficult to apply general routing algorithms to dynamic LEO networks due to the frequent changes in satellite topology caused by the disconnection between moving satellites. Deep reinforcement learning (DRL) models trained by various dynamic networks can be considered. However, since the inference process with the DRL model requires too long a computation time due to multiple convolutional layer operations, it is not practical to apply to a real-time on-board computer (OBC) with limited computing resources. To solve the problem, this paper proposes a practical co-design method with heterogeneous processors to parallelize and accelerate a part of the multiple convolutional layer operations on a field-programmable gate array (FPGA). The proposed method was tested with a real heterogeneous processor-based OBC and showed that the proposed method was about 3.10 times faster than the conventional method while achieving the same routing results. [ABSTRACT FROM AUTHOR]

Increasing fruit crop production sustainability under climate change, particularly increasing temperatures, is a major challenge in modern agriculture. High temperatures affect apple fruit quality and decrease its color. Herein, we constructed an experimental field under temperature simulation to evaluate climate change mitigation strategies for apples. 'Hongro' apples were subjected to three treatments: (1) cultivation inside a vinyl house for heat treatment (heat induction), (2) cultivation under water irrigation (heat reduction), and (3) cultivation under normal atmospheric temperature (control). At harvest, the fruits of the heat treatment group exhibited poor coloration, with a lower gene expression and pigment accumulation than those of the water irrigation and control groups. Furthermore, the fruit quality of the heat treatment group decreased, with a lower soluble solid content (SSC) and titratable acidity (TA), and smaller fruits. Additionally, a higher fruit disorder (cracking and spots) ratio was observed in the heat treatment group than in the water irrigation and control groups. However, the fruits of the water irrigation group exhibited higher quality indexes (flesh firmness, SSC, and TA) and less cracking than those of the heat treatment and control groups. Heat reduction, including water irrigation, may be used for orchard management to prevent climate change-induced increasing temperatures. [ABSTRACT FROM AUTHOR]

C24H18N4O4, monoclinic, P21/c (no. 14), a = 16.5930(5) Å, b = 5.7298(2) Å, c = 20.8714(6) Å, β = 99.8620(10)°, V = 1955.02(11) Å3, Z = 4, Rgt(F) = 0.0415, wRref(F2) = 0.1115, T = 193 K.

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×. [ABSTRACT FROM AUTHOR]

Coloration, a major factor contributing to apple quality, attracts consumer attraction, thereby increasing the sale of fruits in the market. Among the fruit pigments, anthocyanins and carotenoids are the most important pigments that impart coloration to apples. Pigment accumulation, which is regulated by transcriptional factors in the anthocyanin and carotenoid biosynthesis pathways, varies according to genetics, transcription, and developmental stage. To understand the regulation of color development in apples, we evaluated the expression of the genes in the anthocyanin and carotenoid biosynthetic pathways and analyzed the accumulation of pigment, including anthocyanin and carotenoid in the skin and flesh of the red-fleshed apple 'Enbu' cultivar at different fruit development stages (30, 60, 90, 120, and 150 days after full bloom, and ripe). Color development increased according to the developmental stage, with considerable variation in both the transcript levels and pigment concentrations observed in tissues, skin, and flesh. Moreover, we identified key transcription factors among the anthocyanin and carotenoid biosynthesis genes that regulated pigment accumulation. Pearson's correlation analysis showed a strong correlation between the coloration patterns and the expression levels of anthocyanin biosynthesis-related genes (MdPAL, MdCHI, and MdF3H) and carotenoid biosynthesis-related genes (MdGGPPS, MdPSY, MdZDS, MdCRTISO, MdCRHβ, and MdZEP). This study provides insight into the molecular mechanisms underlying pigment biosynthesis for breeding high-quality red-fleshed apple varieties to cater to consumer attention and preference. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Apple skin color is essential for market value. Therefore, this study evaluated the efficiency of pneumatic defoliation (PD) on the enhancement of red skin color and anthocyanin pigments in 'Picnic' apples. Three weeks before harvesting, apple trees were treated with PD with low- (0.7 bar) and high- (0.9 bar) air pressure at a tractor driving speed of 2 km/h. Undefoliated trees served as controls. Higher leaf defoliation and leaf damage rates were observed in the high-PD treatment than those in the low-PD treatment. Photosynthetically active radiation inside the canopies was the highest in trees subjected to high-pressure PD than in those that underwent low-pressure PD and the controls. At harvest, the fruit color (a*) value, red-colored area, and anthocyanin content in the fruit skin were the highest in the high-PD treatment, intermediate in the low-PD treatment, and the lowest in the control treatments. Additionally, a higher expression of anthocyanin biosynthetic genes was observed in both defoliation treatments, especially under high PD. However, except for higher flesh firmness under low PD, the L* and b* values and fruit quality indices (fruit weight, starch pattern index, titratable acidity, soluble solids content, and sunburn occurrence) were not significantly affected by either PD treatment. In conclusion, PD can be used to enhance skin coloration and anthocyanin pigments in apples; further PD with high air pressure achieved optimum red skin coloration in 'Picnic' apples. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

The decrease in fossil fuel usage and the projected 28% increase in the global energy demand by 2040 are calling for advanced methods to convert modern biomass into fine chemicals. For instance, biomass-derived aldehydes appear as promising substitutes for the chemical and fuel industries. Here, we review electrochemical upgrading of furfural and 5-hydroxymethylfurfural with a focus on catalysis and selectivity mechanisms. We also present hybrid water electrolysis systems for production of hydrogen and chemicals. We discuss electrochemical oxidation or hydrogenation of furfural and 5-hydroxymethylfurfural using metal oxides, noble metals, transition metal nanoparticles and alloys, and nonoxides. We compare electrochemical processes with combustion, chemical, thermochemical, and biochemical processes for biomass conversion. [ABSTRACT FROM AUTHOR]

The electrocatalytic reduction of nitrate waste into ammonia allows both the removal of nitrate contaminants and an alternative production of ammonia compared to the classical Haber–Bosch industrial process. Ammonia is useful in agriculture for manufacturing fertilizers, and as a reagent in pharmaceuticals, metallurgy, explosives, and the textile industry; ammonia is also an energy carrier in the automobile industry for next-generation fuel cells. Here we review the nitrate-to-ammonia conversion by electrocatalysis of industrial and agricultural waste, with focus on catalysts, reaction intermediates, side reactions, and reaction conditions. Electron transfer is facilitated by electrocatalysts with transition metals having occupied d-orbitals with similar energy levels to that of the nitrate lowest unoccupied molecular orbital. Green electro-conversion using carbon-based materials is also discussed. Results show nitrate conversion from 53 to 99.8% and ammonia selectivity from 70 to 97.4%. [ABSTRACT FROM AUTHOR]

The structural information of 3‐cyanoindole ammonia cluster, 3CI(NH3)1, in molecular beams was investigated in the gas phase. We obtained UV–UV hole‐burning spectrum (UV–UV HB) to determine the number of conformers present in the molecular beams and examine their spectral features. As a result, single conformer of 3CI(NH3)1 was observed in the mass‐selected one‐color resonant two‐photon ionization (1C‐R2PI) spectroscopy. The origin band of 3CI(NH3)1 in the R2PI spectrum is redshifted by 122 and 71 cm−1 compared to those of the 3CI monomer and 3CI 1:1 water cluster, 3CI(H2O)1, respectively. The fully optimized geometries, relative energies, transition energies, binding energies, and electrostatic potential (ESP) of the 3CI monomer, 3CI(H2O)1, and 3CI(NH3)1 clusters were calculated at the B3LYP and TD‐B3LYP methods with the 6‐311++(d,p) basis set. The observed spectra are compared with the predictions of time‐dependent density functional theory calculations. [ABSTRACT FROM AUTHOR]

A nondestructive testing device, consisting of a scanner and signal processing circuits was developed to detect cracks in turbine disk roots. The scanner consists of a longitudinal feeder and a fir-tree-shaped sensor probe. The feeder inserted the sensor probe along the grooves of the turbine blade attachment. Meanwhile, permanent magnets were placed in opposite direction, to generate a closed magnetic field between the magnetic sensors located on the crests of the sensor probe. The fatigue crack in the turbine disk root occurred in the circumferential direction of the turbine. As a result, magnetic flux leakage was caused by disturbing the flow of closed magnetic field by permanent magnets. The magnetic flux leakage was measured by a magnetic sensor. The effectiveness of the proposed device has been verified using artificial defects introduced into the turbine disk roots by electric discharge machining. [ABSTRACT FROM AUTHOR]

[Cs+(Cryptand[2.2.2])]I− (1; Cryptand[2.2.2] = C222) was characterized via single‐crystal X‐ray diffraction and was shown to crystallize in the monoclinic space group I2/c system with a = 8.9605 (2), b = 23.5073 (5), c = 11.7563 (3) Å, and β = 93.792 (2)°. Stationary and magic angle spinning (MAS) experiments under different magnetic fields allowed for the separation of the chemical shift and quadrupole coupling tensor parameters. Remarkably, MAS spectra showing pure second‐order quadrupole powder patterns at 4.23 T were observed for 133Cs nuclei with small quadrupole moments owing to the large electric field gradients (EFGs) caused by short CsO and CsN bond distances in the [Cs+(C222)] ions. Stationary NMR powder patterns with a combination of the chemical shifts and second‐order quadrupolar interactions were observed. The EFG and chemical shift tensor components calculated using the atomic coordinate files and Gaussian 09 were reasonably consistent with the experimental values. [ABSTRACT FROM AUTHOR]

C24H18N4O4, monoclinic, P21/c (no. 14), a = 16.5930(5) Å, b = 5.7298(2) Å, c = 20.8714(6) Å, β = 99.8620(10)°, V = 1955.02(11) Å3, Z = 4, Rgt(F) = 0.0415, wRref(F2) = 0.1115, T = 193 K. [ABSTRACT FROM AUTHOR]

C24H18N4O4, monoclinic, P21/c (no. 14), a = 16.5930(5) Å, b = 5.7298(2) Å, c = 20.8714(6) Å, β = 99.8620(10)°, V = 1955.02(11) Å3, Z = 4, Rgt(F) = 0.0415, wRref(F2) = 0.1115, T = 193 K. [ABSTRACT FROM AUTHOR]

Establishing appropriate heatwave thresholds is important in reducing adverse human health consequences as it enables a more effective heatwave warning system and response plan. This paper defined such thresholds by focusing on the non-linear relationship between heatwave outcomes and meteorological variables as part of an inductive approach. Daily data on emergency department visitors who were diagnosed with heat illnesses and information on 19 meteorological variables were obtained for the years 2011 to 2016 from relevant government agencies. A Multivariate Adaptive Regression Splines (MARS) analysis was performed to explore points (referred to as “knots”) where the behaviour of the variables rapidly changed. For all emergency department visitors, two thresholds (a maximum daily temperature ≥ 32.58°C for 2 consecutive days and a heat index ≥ 79.64) were selected based on the dramatic rise of morbidity at these points. Nonetheless, visitors, who included children and outside workers diagnosed in the early summer season, were reported as being sensitive to heatwaves at lower thresholds. The average daytime temperature (from noon to 6 PM) was determined to represent an alternative threshold for heatwaves. The findings have implications for exploring complex heatwave-morbidity relationships and for developing appropriate intervention strategies to prevent and mitigate the health impact of heatwaves. [ABSTRACT FROM AUTHOR]

Abstract: Pentamethylcyclopentadienyl (Cp*)‐based Group 9 metal (Co, Rh, or Ir) catalysts have emerged as powerful tools for C−H functionalization reactions. Whilst a diverse range of organic transformations have been developed by using [Cp*MIII] catalysts, they have often exhibited orthogonal reactivities and varied selectivities that depended on the choice of the central metal atom. An understanding of the physicochemical properties of the metals, as well as of their reaction mechanisms, has led to significant expansion of the synthetic scope of C−H functionalization reactions. This Focus Review summarizes and discusses the comparative catalytic reactivities and selectivities of the [Cp*MIII] catalysts, with an emphasis on metal‐dependent pathway‐switching by considering the mechanistic rationale. [ABSTRACT FROM AUTHOR]

[Display omitted] • Acoustic levitation coupled with pulsed laser irradiation process. • Free-standing nanocatalysts synthesis via hybrid acoustic levitation/PLI process. • Au NPs showed excellent catalytic behavior towards 4-nitrophenol reduction. • Formation of NPs and chemical reactions monitored by in situ spectroscopic techniques. 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 ∼ 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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

A procedure for the [Cp*CoIII]-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. [ABSTRACT FROM AUTHOR]

The B(C6F5)3-catalyzed silylative reduction of conjugated nitriles has been developed to afford synthetically valuable β-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 β-silyl amine, thus forming a new C(sp3)Si bond. Based on this mechanistic understanding, a preparative route to enamines was also established using bulky silanes. [ABSTRACT FROM AUTHOR]

A new synthetic routeto phosphoramidates by intermolecular C–Hamidation is presented. Substrates with assorted directing groupswere activated by an iridium-based catalyst system and reacted witha number of phosphoryl azides, executing efficient phosphoramidatesynthesis via C–N bond formations. [ABSTRACT FROM AUTHOR]

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−, SO 4 2−, and NO 3 −) 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. • Zn@ZnO core shell was prepared by pulsed laser ablation method. • Zn@ZnO based electrochemical sensor was developed for hydroquinone detection. • Fabricated sensor exhibits high sensitivity with LOD of 0.10 μM in 10–90 μM range. • Excellent selectivity and stability were observed from Zn@ZnO towards HQ. [ABSTRACT FROM AUTHOR]

Two kinds of low-band gap polymers, poly[{N-(1-octyldecyl)-2,7-carbazole)}-alt-{1,7- di(4-tert-butylphenyloxy)-3,4,9,10-perylenebis(dicarboximide)-N,N′-di(2,6-dimethyl- phenyl-4-yl)}] poly(Cvz-PDIMEP) and poly{[N,N′-di(10-nonadecyl)perylene-3,4,9, 10-tetracarboxylic acid diimide-1,7-diyl]-alt-(9-heptadecyl)-9H-carbazol-2-yl)} poly (Cvz-PDIC9), were synthesized by palladium-catalyzed Suzuki polymerization. Bulk heterojunction solar cells with an ITO/PEDOT/polymer:PC71BM/LiF/Al configuration were fabricated, which shows short-circuit current density, open-circuit voltage, fill factor, and power conversion efficiency of 0.85 mA/cm2, 0.32 V, 0.27, and 0.073% under AM 1.5 irradiation (100 mW/cm2), respectively. [ABSTRACT FROM PUBLISHER]

Abstract: We fabricated highly efficient solution processed red phosphorescent organic light-emitting diodes (PhOLEDs) composed of bis[9-ethyl-3-(4-phenylquinolin-2-yl)-9H-carbazolato-N,C 2′]iridium picolinate N-oxide (Et-CVz-PhQ)2Ir(pic-N-O) and bis[9-(2-(2-methoxyethoxy)ethyl)-3-(4-phenylquinolin-2-yl)-9H-carbazolato-N,C 2′]iridium picolinate N-oxide (EO-CVz-PhQ)2Ir(pic-N-O) as an emitter, which were doped into poly(N-vinylcarbazole) (PVK), electron transport material, 1,3-bis[2-(4-tert-butylphenyl)-1,3,4-oxadiazo-5-yl]benzene (OXD-7) and optimized concentration of hole transport material, N,N′-diphenyl-N,N′-(bis(3-methylphenyl)-[1,1-biphenyl]-4,4′-diamine (TPD). The optimized PhOLEDs doped with 16wt% of TPD shows a maximum external quantum efficiency of 9.21% and a luminance efficiency of 15.24cd/A with a CIE coordinate of (0.62,0.38). [Copyright &y& Elsevier]

A straightforward protocol towards biologically important 7-aminoindoles is developed. [ABSTRACT FROM AUTHOR]

An abstract of the article "Comparative Catalytic Activity of Group 9 [Cp*MIII] Complexes: Cobalt-Catalyzed C-H Amidation of Arenes with Dioxazolones as Amidating Reagents" by Park J and Chang S. is presented.

In the presence of excess diphenyl and triphenyl silane acryl nitriles are reduced to silyl amines and N-disilyl enamines. [ABSTRACT FROM AUTHOR]

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 (MoS 2), a layered dichalcogenide material exhibiting unique properties, in combination with graphitic carbon nitride (g-C 3 N 4), a carbon-based layered material, was fabricated with small amounts of zinc oxide (ZnO). Three composites, MoS 2 /g-C 3 N 4 , MoS 2 /ZnO, and MoS 2 /g-C 3 N 4 /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. [ABSTRACT FROM AUTHOR]