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Practical copper-promoted N-alkylation and bromination of arylamines/indazoles with alkyl bromides are described; the N-alkylation-C-4-bromination and N-dialkylation-C-4-bromination of arylamines, and N-alkylation-C-3-bromination of indazoles, with alkyl bromides have been analyzed. The full use of alkyl bromides as alkylating and brominating building blocks without atom wastage, indicating excellent atom and step economy, has been highlighted. Eco-friendly oxygen and water are the reaction oxidant and byproduct, respectively.
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Bromuros , Cobre , Alquilación , Aminas , Halogenación , Indazoles , Indicadores y Reactivos , Oxidantes , Oxígeno , AguaRESUMEN
Real-time video perception tasks are often challenging on resource-constrained edge devices due to the issues of accuracy drop and hardware overhead, where saving computations is the key to performance improvement. Existing methods either rely on domain-specific neural chips or priorly searched models, which require specialized optimization according to different task properties. These limitations motivate us to design a general and task-independent methodology, called Patch Automatic Skip Scheme (PASS), which supports diverse video perception settings by decoupling acceleration and tasks. The gist is to capture inter-frame correlations and skip redundant computations at patch level, where the patch is a non-overlapping square block in visual. PASS equips each convolution layer with a learnable gate to selectively determine which patches could be safely skipped without degrading model accuracy. Specifically, we are the first to construct a self-supervisory procedure for gate optimization, which learns to extract contrastive representations from frame sequences. The pre-trained gates can serve as plug-and-play modules to implement patch-skippable neural backbones, and automatically generate proper skip strategy to accelerate different video-based downstream tasks, e.g., outperforming state-of-the-art MobileHumanPose in 3D pose estimation and FairMOT in multiple object tracking, by up to 9.43 × and 12.19 × speedups, respectively, on NVIDIA Jetson Nano devices.
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Hyperuricemic nephropathy (HN) is characterized by renal fibrosis and tubular necrosis caused by elevated uric acid levels. Ferroptosis, an iron-dependent type of cell death, has been implicated in the pathogenesis of kidney diseases. The objective of this study was to explore the role of ferroptosis in HN and the impact of a ferroptosis inhibitor, ferrostatin-1 (Fer-1). The study combined adenine and potassium oxonate administration to establish a HN model in mice and treated HK-2 cells with uric acid to simulate HN conditions. The effects of Fer-1 on the renal function, fibrosis, and ferroptosis-associated molecules were investigated in HN mice and HK-2 cells treated with uric acid. The HN mice presented with renal dysfunction characterized by elevated tissue iron levels and diminished antioxidant capacity. There was a significant decrease in the mRNA and protein expression levels of SLC7A11, GPX4, FTL-1 and FTH-1 in HN mice. Conversely, treatment with Fer-1 reduced serum uric acid, serum creatinine, and blood urea nitrogen, while increasing uric acid levels in urine. Fer-1 administration also ameliorated renal tubule dilatation and reduced renal collagen deposition. Additionally, Fer-1 also upregulated the expression levels of SLC7A11, GPX4, FTL-1, and FTH-1, decreased malondialdehyde and iron levels, and enhanced glutathione in vivo and in vitro. Furthermore, we first found that Fer-1 exhibited a dose-dependent inhibition of URAT1, with the IC50 value of 7.37 ± 0.66 µM. Collectively, the current study demonstrated that Fer-1 effectively mitigated HN by suppressing ferroptosis, highlighting the potential of targeting ferroptosis as a therapeutic strategy for HN.
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Ciclohexilaminas , Ferroptosis , Hiperuricemia , Enfermedades Renales , Fenilendiaminas , Ratones , Animales , Ácido Úrico , Hiperuricemia/tratamiento farmacológico , Hiperuricemia/metabolismo , Enfermedades Renales/tratamiento farmacológico , Fibrosis , HierroRESUMEN
Extreme myopia (EM), defined as a spherical equivalent (SE) ≤ -10.00 diopters (D), is one of the leading causes of sight impairment. Known EM-associated variants only explain limited risk and are inadequate for clinical decision-making. To discover risk genes, we performed a whole-exome sequencing (WES) on 449 EM individuals and 9606 controls. We find a significant excess of rare protein-truncating variants (PTVs) in EM cases, enriched in the retrograde vesicle-mediated transport pathway. Employing single-cell RNA-sequencing (scRNA-seq) and a single-cell polygenic burden score (scPBS), we pinpointed PI16 + /SFRP4+ fibroblasts as the most relevant cell type. We observed that KDELR3 is highly expressed in scleral fibroblast and involved in scleral extracellular matrix (ECM) organization. The zebrafish model revealed that kdelr3 downregulation leads to elongated ocular axial length and increased lens diameter. Together, our study provides insight into the genetics of EM in humans and highlights KDELR3's role in EM pathogenesis.
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Secuenciación del Exoma , Mutación , Pez Cebra , Humanos , Animales , Pez Cebra/genética , Masculino , Femenino , Fibroblastos/metabolismo , Exoma/genética , Estudio de Asociación del Genoma Completo , Adulto , Miopía/genética , Miopía/metabolismo , Miopía/patología , Esclerótica/metabolismo , Esclerótica/patología , Matriz Extracelular/metabolismo , Matriz Extracelular/genética , Predisposición Genética a la Enfermedad , Análisis de la Célula Individual , Estudios de Casos y Controles , Niño , Adulto JovenRESUMEN
To guarantee the transporting efficiency of microdevices associated with fluid transportation, mixing, or separation and to promote the heat transfer performance of heat exchangers in microelectronics, the hydrodynamic behaviors at unsteady and steady states, as well as the thermal characteristics at the steady state in a pressure-driven electrokinetic slip flow of power-law fluid in a microannulus are studied. To present a more reliable prediction, the slip phenomenon at walls and nonlinear rheology of liquid are incorporated. The modified Cauchy momentum equation applicable to all time scales and energy equations, are analytically solved in the limiting case of a Newtonian fluid and numerically solved for power-law fluids. The transient velocity profile, time evolution of flow rate, temperature profile, and heat transfer rate are computed at different flow behavior indices, electrokinetic width, slip lengths, and Brinkman numbers, thereby, the coupling effect of nonlinear rheology, slip hydrodynamics, and annular geometry on flow and thermal behaviors is explored. The unsteady flow takes a longer time to achieve the steady state for shear thinning fluids or greater slip lengths. The flow behavior index and slip length play a significant role in the flow rate and heat transfer performance. The relevant discussion can serve as a theoretical guide for the operation and thermal management of annular geometry-related flow actuation systems.
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In this article, an adaptive sliding-mode disturbance observer (ASMDO)-based finite-time control scheme with prescribed performance is proposed for an unmanned aerial manipulator (UAM) under uncertainties and external disturbances. First, to take into account the dynamic characteristics of the UAM, a dynamic model of the UAM with state-dependent uncertainties and external disturbances is introduced. Then, note that a priori bounded uncertainty may impose a priori constraint on the system state before obtaining closed-loop stability. To remove this assumption, an ASMDO with a nested adaptive structure is introduced to effectively estimate and compensate the external disturbances and state-dependent uncertainties in finite time without the information of the upper bound of the uncertainties and disturbances and their derivatives. Furthermore, based on the proposed ASMDO, the finite-time control scheme with the prescribed performance is presented to ensure finite-time convergence and implement the specified transient and steady-state performance. The Lyapunov tools are utilized to analyze the stability of the proposed controller. Finally, the correctness and performance of the proposed controller are illustrated through numerical simulation comparisons and outdoor experimental comparisons.
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The relationship between the Kerguelen mantle plume and the breakup of eastern Gondwana is still debated. The new Zircon SHRIMP U-Pb dating of 139.9 ± 4.6 Ma, as well as previous ages from the Zhela Formation volcanic rocks in the Tethyan Himalaya, show that the studied Zhela Formation volcanic rocks formed during the Late Jurassic-Early Cretaceous, rather than the Middle Jurassic. The calculated volume of the Comei-Bunbury igneous rocks is ~ 114,250 km3, which is compatible with the large igneous provinces and, consequently, the typical mantle plume models. The new date results, along with existing dates, show that the volcanism attributed to the Kerguelen mantle plume in the Tethyan Himalaya ranges from ca.147 Ma to ca.124 Ma, with two peaks at approximately 141 Ma and 133 Ma. This new finding, together with geochemical and palaeomagnetic data obtained from the Comei-Bunbury igneous rocks, indicate that the Kerguelen mantle plume contributed significantly to the breakup of eastern Gondwana and that eastern Gondwana first disintegrated and dispersed at ca.147 Ma, the Indian plate separated completely from the eastern Gondwana before ca.125 Ma.
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Alkali metal transition oxide LiCoO2 has been successfully commercialized as a lithium-ion battery material, and some attention is paid to its homologous derivatives LiRhO2 and LiIrO2. However, the photocatalytic properties have not been explored yet for these compounds. Using the first-principles calculations, we carry out investigations on the electronic properties, light absorption, and mobility to understand the feasibility of LiXO2(X = Co, Rh, Ir) for solar light photocatalytic hydrogen generation from water-splitting. The results show that the band edges of LiCoO2 and LiRhO2 meet the redox potential requirements of the water-splitting hydrogen evolution reaction. In addition, the enhanced absorptions of LiXO2(X = Co, Rh, Ir) in the visible light range imply that they could well respond to solar light, while the significant difference in the mobilities of electrons or holes can strengthen spatial charge separation of the photoexcited electron-hole pairs. The solar-energy-to-hydrogen conversion efficiencies of LiCoO2 and LiRhO2 can reach 11.2% and 15.5%, respectively. The results support LiCoO2 and LiRhO2 as promising candidates for visible-light photocatalytic hydrogen production from water-splitting.
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We synthesized a temperature-sensitive antibacterial hydrogel, defined as NIPAM-CG/GM hydrogel. First, vinyl carboxymethyl chitosan (CG) was synthesized as a crosslinking carrier and silane dispersed graphene (GM) was synthesized as a reinforcer. Then, the N-isopropylacrylamide (NIPAM) monomer was free-radical polymerized with the vinyl groups of CG and GM to form a NIPAM-CG/GM hydrogel without any crosslinking agent. The influences of different hydrogel compositions on the microstructure, compressive properties, swelling, drug loading, and drug release properties of the hydrogels were discussed, and its temperature sensitivity was also demonstrated. The results showed that the lower critical solution temperature (LCST) and mechanical properties of the hydrogel could be adjusted by controlling the amount of CG and GM. Next, its biocompatibility was characterized, and its antibacterial performance was tested against Escherichia coli and Staphylococcus aureus. The antibacterial mechanism was explained by measuring the difference in the ion concentration outside the membrane and changes in the morphology of live/dead bacteria. NIPAM-CG/GM had a high drug loading and nearly complete drug release at a physiological temperature of 37 °C. Its moderate mechanical properties, excellent biocompatibility, and antibacterial effects give NIPAM-CG/GM great potential applications as a wound dressing.
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HidrogelesRESUMEN
The photocatalytic properties of LiCoO2 are not explored up to date although its cubic and trigonal structures are explored experimentally. Here, we investigate the feasibility of photocatalytic hydrogen production from water splitting driven by the tetragonal, trigonal, hexagonal and cubic LiCoO2 with the irradiation of the visible light. The band structure, density of state, optical absorption and mobility are calculated by the first-principles density functional theory. The results show that the band edges of all the four structures of LiCoO2 match to the conditions of the redox potentials of water splitting reaction and the enhanced optical absorption in the visible light range is observed. The obvious difference between the mobilities of the hole and electron are identified, especially for the cubic LiCoO2. All the obtained results suggest that the considered structures of LiCoO2 are promising candidates for the photocatalytic water splitting to produce hydrogen with the irradiation of the visible light.
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The temporal and spatial distribution characteristics, evolution trend and potential climatic effects of air pollution in the Guangdong-Hong Kong-Macao Greater Bay Area (GBA) were analyzed on different time scales and spatial spaces, based on ground environment observation data from June 2014 to December 2018 and satellite remote sensing inversion products from 2000 to 2018. The results show that:â From the in-situ observed daily average concentration of PM2.5, good or mild to moderate pollution occurred in January, February, October, November, and December every year, and the rest of the time was excellent. â¡ Based on the annual average PM2.5 concentration obtained by satellite for the past 20 years, the spatial characteristics showed that the external radiation is centered on Guangzhou and Foshan. The time evolution shows the characteristics of an Ω shape, which increases gradually from 2000 to 2009, is highest in 2008, and then gradually decreases. ⢠The monthly average aerosol optical thickness (AOT) value from the Multi-angle Imaging Spectro Radiometer satellite reversion every 10 years for a period (2000-2009 for a period, 2010-2018 for a period) was used to see the monthly variation. The monthly average AOT value in the first period was larger than that in the second period of the same month, the maximum value was in March and April, and the minimum value was in November and December. It is envisaged to draw a line along the north-south direction of the Pearl River Port, which basically shows that the AOT value in the west is greater than that in the east. ⣠According to the observed daily average concentration data of O3-8h, the main concentration level of O3-8h in the GBA is excellent. The cities with good ozone concentration were most numerous in 2014, with five cities, and least in 2018, with only one city. The highest ozone concentration was in September, followed by June and November, and then May and July. In the past 20 years, the spatial distribution of the average concentration of O3 monitored by satellite remote sensing showed a characteristic Ω shape, increasing initially and then decreasing. The maximum value was in May, and the north-south boundary line appeared in space. ⤠There is a good linear relationship between the interannual variation of monthly mean temperature and radiation, whereas the relationship between AOT and radiation cannot be described by a simple linear relationship.
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The analysis of veterinary drugs in organic fertilizers is crucial for an assessment of their potential risks to microbial communities in soils and to human health. A method has been developed for the simultaneous determination of ten fluoroquinolones in organic fertilizers by using the QuEChERS method coupled with high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). The sample was extracted with disodium ethylenediaminetetraacetic acid (Na2EDTA)-McIlvaine buffer (pH=4.0) and acetonitrile. The target compounds were separated on an Atlantis T3 C18 column (250 mm×4.6 mm, 5 µm) with a mobile phase of 0.2% (v/v) formic acid in acetonitrile and analyzed in the multiple reaction monitoring (MRM) mode via electrospray ionization (ESI). Ten fluoroquinolones were quantified by an internal standard method. The calibration curves of the ten fluoroquinolones exhibited good linearity over the range of 10-500 µg/kg, and the correlation coefficients were above 0.9930. The limits of detection were 0.5-2.5 µg/kg; the limits of quantification were 1.7-8.3 µg/kg. The analytical method was successfully applied in a survey of veterinary drug contamination in nine compost samples. The average recoveries were 82.5%-117.1%, with relative standard deviations of 3.4%-10.2%. The method is accurate, reliable, and sensitive and supports the simultaneous detection of various veterinary drug residues. Therefore, this method can provide a basis for the risk assessment of veterinary drugs in organic fertilizers.
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Residuos de Medicamentos/análisis , Fertilizantes/análisis , Fluoroquinolonas/análisis , Drogas Veterinarias/análisis , Cromatografía Líquida de Alta Presión , Compostaje , Espectrometría de Masas en TándemRESUMEN
The object of this study was to investigate the effect of saturated zone depth (SZD) and plant on the removal of organics and nitrogen in four continuous-feed vertical flow-constructed wetlands (VFCWs). Three VFCWs were planted with Iris pseudacorus and operated at different SZDs (19, 51, and 84 cm), and the other one was non-planted and operated at 51 cm SZD. The VFCWs were operated with an organic loading rate (OLR) of 79 g chemical oxygen demand (COD) m-2 day-1, a total nitrogen loading rate (NLR) of 11 g N m-2 day-1, and a hydraulic loading rate (HLR) of 0.35 m3 m-2 day-1. Simultaneous transformation of ammonium and nitrate occurred in all of the four systems. In the planted bed with 51 cm SZD, suitable conditions for nitrification and denitrification could be created and the best performance for total nitrogen (TN) removal was realized via simultaneous nitrification and denitrification (SND), achieving TN removal efficiency of 67.4-80.3%. Higher ammonium nitrogen (NH4+-N) and COD removal efficiency was obtained in the system operated with 19 cm SZD, whereas higher NO3--N removal could be achieved in the bed with 84 cm SZD. With the same SZD of 51 cm, the planted VFCW performed preferable removal of COD, NH4+-N, and TN in comparison with the non-planted one. All the VFCWs showed high removal efficiencies for total phosphorus (> 60.15%). Adsorption of phosphorus was primarily observed in the top and upper-middle layers filled with carbon burn slag. It has been proved that the partially saturated VFCW operated with continuous feed could achieve good performance in removal of organic matter and nitrogen by SZD adjustment to develop appropriate aerobic and anoxic regions.