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1.
BMC Plant Biol ; 24(1): 409, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38760736

RESUMO

BACKGROUND: Bletilla striata (Thunb.) Reichb. f. (B. striata) is a perennial herbaceous plant in the Orchidaceae family known for its diverse pharmacological activities, such as promoting wound healing, hemostasis, anti-inflammatory effects, antioxidant properties, and immune regulation. Nevertheless, the microbe-plant-metabolite regulation patterns for B. striata remain largely undetermined, especially in the field of rhizosphere microbes. To elucidate the interrelationships between soil physics and chemistry and rhizosphere microbes and metabolites, a comprehensive approach combining metagenome analysis and targeted metabolomics was employed to investigate the rhizosphere soil and tubers from four provinces and eight production areas in China. RESULTS: Our study reveals that the core rhizosphere microbiome of B. striata is predominantly comprised of Paraburkholderia, Methylibium, Bradyrhizobium, Chitinophaga, and Mycobacterium. These microbial species are recognized as potentially beneficial for plants health. Comprehensive analysis revealed a significant association between the accumulation of metabolites, such as militarine and polysaccharides in B. striata and the composition of rhizosphere microbes at the genus level. Furthermore, we found that the soil environment indirectly influenced the metabolite profile of B. striata by affecting the composition of rhizosphere microbes. Notably, our research identifies soil organic carbon as a primary driving factor influencing metabolite accumulation in B. striata. CONCLUSION: Our fndings contribute to an enhanced understanding of the comprehensive regulatory mechanism involving microbe-plant-metabolite interactions. This research provides a theoretical basis for the cultivation of high-quality traditional Chinese medicine B. striata.


Assuntos
Microbiota , Orchidaceae , Rizosfera , Microbiologia do Solo , Orchidaceae/microbiologia , Orchidaceae/metabolismo , China , Tubérculos/microbiologia , Tubérculos/metabolismo
2.
Small ; 20(28): e2307323, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38349049

RESUMO

Layered zeolitic silicates and corresponding interlayer-expanded porous materials exhibit attractive application potential in wide fields. Nonetheless, designable synthesis and structure analysis of layered silicates remain challenging. Herein, two kinds of layered silicates are synthesized using different di-quaternary ammonium-type organic structure-directing agents (OSDAs). Their crystal structures are analyzed and verified by 3D electron diffraction (3D ED) and high-resolution TEM imaging. The suitable configurations of OSDA can lead to desirable interlayer states. Additionally, two new zeolite structures both with 12-membered ring (MR) channels intersected by 8 MR channels and larger interlayer spaces are constructed from layered silicate precursors by interlayer silylation. The new zeolitic material exhibits potential application in adsorption of organic pollution and catalytic reaction. This study is expected to develop versatile ways for the design and synthesis of layered silicates even zeolites and provide references in characterizing layered materials and zeolites as well.

3.
Nature ; 555(7696): 363-366, 2018 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-29513654

RESUMO

Sustainably feeding a growing population is a grand challenge, and one that is particularly difficult in regions that are dominated by smallholder farming. Despite local successes, mobilizing vast smallholder communities with science- and evidence-based management practices to simultaneously address production and pollution problems has been infeasible. Here we report the outcome of concerted efforts in engaging millions of Chinese smallholder farmers to adopt enhanced management practices for greater yield and environmental performance. First, we conducted field trials across China's major agroecological zones to develop locally applicable recommendations using a comprehensive decision-support program. Engaging farmers to adopt those recommendations involved the collaboration of a core network of 1,152 researchers with numerous extension agents and agribusiness personnel. From 2005 to 2015, about 20.9 million farmers in 452 counties adopted enhanced management practices in fields with a total of 37.7 million cumulative hectares over the years. Average yields (maize, rice and wheat) increased by 10.8-11.5%, generating a net grain output of 33 million tonnes (Mt). At the same time, application of nitrogen decreased by 14.7-18.1%, saving 1.2 Mt of nitrogen fertilizers. The increased grain output and decreased nitrogen fertilizer use were equivalent to US$12.2 billion. Estimated reactive nitrogen losses averaged 4.5-4.7 kg nitrogen per Megagram (Mg) with the intervention compared to 6.0-6.4 kg nitrogen per Mg without. Greenhouse gas emissions were 328 kg, 812 kg and 434 kg CO2 equivalent per Mg of maize, rice and wheat produced, respectively, compared to 422 kg, 941 kg and 549 kg CO2 equivalent per Mg without the intervention. On the basis of a large-scale survey (8.6 million farmer participants) and scenario analyses, we further demonstrate the potential impacts of implementing the enhanced management practices on China's food security and sustainability outlook.


Assuntos
Agricultura/métodos , Conservação dos Recursos Naturais , Produtos Agrícolas/crescimento & desenvolvimento , Eficiência Organizacional , Fazendeiros , China , Técnicas de Apoio para a Decisão , Grão Comestível/crescimento & desenvolvimento , Política Ambiental , Fertilizantes/estatística & dados numéricos , Abastecimento de Alimentos/métodos , Efeito Estufa , Nitrogênio/metabolismo , Oryza/crescimento & desenvolvimento , Triticum/crescimento & desenvolvimento , Zea mays/crescimento & desenvolvimento
4.
BMC Urol ; 24(1): 5, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38172816

RESUMO

OBJECTIVES: The aim of this study was to use deep learning (DL) of intraoperative images of urinary stones to predict the composition of urinary stones. In this way, the laser frequency and intensity can be adjusted in real time to reduce operation time and surgical trauma. MATERIALS AND METHODS: A total of 490 patients who underwent holmium laser surgery during the two-year period from March 2021 to March 2023 and had stone analysis results were collected by the stone laboratory. A total of 1658 intraoperative stone images were obtained. The eight stone categories with the highest number of stones were selected by sorting. Single component stones include calcium oxalate monohydrate (W1), calcium oxalate dihydrate (W2), magnesium ammonium phosphate hexahydrate, apatite carbonate (CH) and anhydrous uric acid (U). Mixed stones include W2 + U, W1 + W2 and W1 + CH. All stones have intraoperative videos. More than 20 intraoperative high-resolution images of the stones, including the surface and core of the stones, were available for each patient via FFmpeg command screenshots. The deep convolutional neural network (CNN) ResNet-101 (ResNet, Microsoft) was applied to each image as a multiclass classification model. RESULTS: The composition prediction rates for each component were as follows: calcium oxalate monohydrate 99% (n = 142), calcium oxalate dihydrate 100% (n = 29), apatite carbonate 100% (n = 131), anhydrous uric acid 98% (n = 57), W1 + W2 100% (n = 82), W1 + CH 100% ( n = 20) and W2 + U 100% (n = 24). The overall weighted recall of the cellular neural network component analysis for the entire cohort was 99%. CONCLUSION: This preliminary study suggests that DL is a promising method for identifying urinary stone components from intraoperative endoscopic images. Compared to intraoperative identification of stone components by the human eye, DL can discriminate single and mixed stone components more accurately and quickly. At the same time, based on the training of stone images in vitro, it is closer to the clinical application of stone images in vivo. This technology can be used to identify the composition of stones in real time and to adjust the frequency and energy intensity of the holmium laser in time. The prediction of stone composition can significantly shorten the operation time, improve the efficiency of stone surgery and prevent the risk of postoperative infection.


Assuntos
Cálculos Renais , Cálculos Urinários , Humanos , Oxalato de Cálcio , Cálculos Renais/diagnóstico por imagem , Cálculos Renais/cirurgia , Ácido Úrico , Apatitas , Aprendizado de Máquina , Carbonatos
5.
Urol Int ; 108(2): 100-107, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38081150

RESUMO

INTRODUCTION: Bladder cancer (BC) is a major health concern that poses a significant threat to the population, with an increasing incidence rate and a high risk of recurrence and progression. The primary clinical method for diagnosing BC is cystoscopy, but due to the limitations of traditional white light cystoscopy and inadequate clinical experience among junior physicians, its detection rate for bladder tumor, especially small and flat lesions, is relatively low. However, recent years have seen remarkable advancements in the application of artificial intelligence (AI) technology in the field of medicine. This has led to the development of numerous AI algorithms that have been successfully integrated into medical practices, providing valuable assistance to clinicians. The purpose of this study is to develop a cystoscopy algorithm that is real time, cost effective, high performing, and accurate, with the aim of enhancing the detection rate of bladder tumors during cystoscopy. MATERIALS AND METHODS: For this study, a dataset of 3,500 cystoscopic images obtained from 100 patients diagnosed with BC was collected, and a deep learning model was developed utilizing the U-Net algorithm within a convolutional neural network for training purposes. RESULTS: This study randomly divided 3,500 images from 100 BC patients into training and validation groups, and each patient's pathology result was confirmed. In the validation group, the accuracy of tumor recognition by the U-Net algorithm reached 98% compared to primary urologists, with greater accuracy and faster detection speed. CONCLUSION: This study highlights the potential of U-Net-based deep learning techniques in the detection of bladder tumors. The establishment and optimization of the U-Net model is a significant breakthrough and it provides a valuable reference for future research in the field of medical image processing.


Assuntos
Inteligência Artificial , Neoplasias da Bexiga Urinária , Humanos , Neoplasias da Bexiga Urinária/diagnóstico , Neoplasias da Bexiga Urinária/patologia , Cistoscopia/métodos , Redes Neurais de Computação , Algoritmos
6.
Nano Lett ; 23(24): 11569-11577, 2023 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-38078629

RESUMO

Creating customizable metallic nanostructures in a simple and controllable manner has been a long-standing goal in nanoscience. In this study, we use DNA origami as a letterpress printing plate and gold nanoparticles as ink to produce predesigned gold nanostructures. The letterpress plate is reusable, enabling the repetitive production of predesigned gold nanostructures. Furthermore, by modifying the DNA origami letterpress plate on magnetic beads, we can simplify the printing processes. We have successfully printed gold nanoparticle dimers, trimers, straight and quadrilateral tetramers, and other nanostructures. Our approach improves the flexibility and stability of metallic nanostructures, simplifying both their design and their operation. It promises universal applicability in the fabrication of metamaterials, biosensors, and surface plasma nanooptics.


Assuntos
Nanopartículas Metálicas , Nanoestruturas , Ouro/química , Nanopartículas Metálicas/química , Nanoestruturas/química , DNA/química , Impressão Tridimensional , Nanotecnologia
7.
Nano Lett ; 23(8): 3326-3333, 2023 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-37026788

RESUMO

On-chip photonic systems play crucial roles in nanoscience and nanoapplications, but coupling external light to these subwavelength devices is challenging due to a large mode mismatch. Here, we establish a new scheme for realizing highly miniaturized couplers for efficiently exciting on-chip photonic devices in a controllable way. Relying on both resonant and Pancharatnam-Berry mechanisms, our meta-device can couple circularly polarized light to a surface plasmon, which is then focused into a spot placed with a target on-chip device. We experimentally demonstrate two meta-couplers. The first can excite an on-chip waveguide (with a 0.1λ × 0.2λ cross section) with an absolute efficiency of 51%, while the second can achieve incident spin-selective excitation of a dual-waveguide system. Background-free excitation of a gap-plasmon nanocavity with the local field enhanced by >1000 times is numerically demonstrated. Such a scheme connects efficiently propagating light in free space and localized fields in on-chip devices, being highly favored in many integration-optics applications.

8.
J Environ Manage ; 351: 119687, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38061097

RESUMO

Ridge-furrow with full film mulching has been widely applied to increase crop yield and water productivity on the Loess Plateau, but it may stimulate carbon (C) mineralization. How to integrate other technological benefits based on this technology for long-term maintenance of high yield and soil fertility is a pressing issue. With the local farmers' practice (FP) as a control, three integrated soil-crop system management (ISSM) practices integrating fertilizer rates, fertilizer types and planting densities (ISSM-N1, ISSM-N2 and ISSM-MN) were established to improve maize yield and soil quality. Compared with the FP, the maize yield increased by 13.34%, 21.83% and 30.24%, and the soil quality index (SQI) increased by 9.66%, 14.91% and 38.38% for ISSM-N1, ISSM-N2 and ISSM-MN, respectively. However, ISSM-N1 did not significantly increase yield, and ISSM-N2 increased residual soil nitrate and decreased nitrogen (N) partial factor productivity significantly. Compared to the FP, ISSM practices increased soil organic carbon (SOC), labile organic C fractions (LOCFs) and potassium permanganate organic C fractions in the topsoil to varying degrees, but only ISSM-MN reached significant levels for most C fractions. The sensitivity index indicated very easily oxidizable C (24.6%), easily oxidizable C (24.7%), hot-water extractable C (30.8%), labile organic C (24.7%) and particulate organic C (57.3%) were more sensitive than SOC (22.7%). ISSM-MN sequestered significantly higher C than the other treatments. The results of the relative importance analysis and the structural equation model indicated that LOCFs were the direct contributors to yield, while recalcitrant C (CO) was the indirect contributor, revealing the underlying mechanism that CO decomposed to replenish LOCFs and the total N pool with the water soluble C pool as the transit station. Overall, ISSM-MN is the most promising strategy to improve crop yield and soil fertility in the long term on the Loess Plateau.


Assuntos
Agricultura , Solo , Solo/química , Agricultura/métodos , Carbono/análise , Fertilizantes/análise , Zea mays , Nitrogênio/análise , Água/análise , China
9.
J Environ Manage ; 351: 119854, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38128212

RESUMO

Controlled-release urea application and straw incorporation have been conducted in recent years as environmental-friendly and sustainable farming strategies, but the long-term effects of controlled-release urea application and combination with straw on the dryland maize yield, soil fertility and the environment under future climate scenarios remain unclear. Hence, based on a six-year field experiment, four treatments were used to calibrate and validate the DeNitrification-DeComposition (DNDC) model, including non-nitrogen (CK), split applications of conventional urea (UR), single basal application of conventional urea and controlled-release urea at a ratio of 2:1 (CU), and CU combined with straw (CUS). Subsequently, coupled the well-validated model with future climate to evaluate suitable agricultural production practices under two shared socioeconomic pathways (SSP)-SSP245 and SSP585. The validation results indicated a good fit between the simulated and observed data of greenhouse gas emissions, soil organic carbon (SOC) contents and maize yields. With the anticipation of warmer temperatures and increased precipitation in the future, the yields of UR, CU, and CUS treatment significantly rose. Under SSP585 scenario, the positive impacts of CU treatment on maize yields reduced after the 2050s, exhibiting an average decline of 12.03%. Compared with the UR treatment, the CU treatment markedly reduced cumulative N2O emissions, and both treatments maintained the original state of SOC storages in the 2030s, furthermore, the CUS treatment reduced N2O emissions by 47.10%, 35.07%, 23.80% and 10.04% in the 2030s, 2050s, 2070s and 2090s, respectively. SOC storages for the CUS treatment gradually increased with an average of 464.58, 350.22, 250.87 and 177.75 kg C ha-1 y-1 for two SSP scenarios in the 2030s, 2050s, 2070s and 2090s, which excellently offset the CO2 equivalent of emissions caused by N2O emissions. Therefore, in dryland maize production, combined controlled-release urea with straw incorporation could achieve the best comprehensive effect among increase of yield, improvement of SOC storages and alleviation of greenhouse gas emissions under future climate scenario.


Assuntos
Gases de Efeito Estufa , Solo , Zea mays , Carbono , Preparações de Ação Retardada , Óxido Nitroso/análise , Agricultura/métodos , Fertilizantes/análise , China
10.
Molecules ; 29(6)2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38543011

RESUMO

Artemisia japonica Thunb. has been used as a traditional Chinese medicine and a vegetable for thousands of years in China. However, there are few reports on the chemical composition and biological activity of its leaves. Thus, this study aimed to evaluate the chemical composition, antioxidant and anti-inflammatory effects of water extracts of A. japonica leaves and their underlying mechanisms. A total of 48 compounds were identified in the water extract using UPLC-QTOF-MS2 analysis, with phenolic acids, particularly chlorogenic acid compounds, being the predominant components. The ethyl acetate fraction (EAF) contained most of the total phenolic content (385.4217 mg GAE/g) and displayed superior antioxidant capacity with the IC50DPPH•, IC50ABTS•+, and OD0.5reducing power at 10.987 µg/mL, 43.630 µg/mL and 26.883 µg/mL, respectively. Furthermore, EAF demonstrated potent antioxidant and anti-inflammatory effects in LPS-induced RAW264.7 cells by upregulating the Nrf2/HO-1 signal pathway. These findings highlight that A. japonica leaves possess remarkable abilities to mitigate inflammation and oxidative stress, suggesting their potential utilization as medicinal agents and food additives for promoting human health.


Assuntos
Antioxidantes , Artemisia , Humanos , Animais , Camundongos , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Lipopolissacarídeos/farmacologia , Extratos Vegetais/química , Artemisia/metabolismo , Transdução de Sinais , Estresse Oxidativo , Anti-Inflamatórios/farmacologia , Água/farmacologia , Células RAW 264.7
11.
Sensors (Basel) ; 23(2)2023 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-36679679

RESUMO

Constant monitoring of driving conditions and observation of the surrounding area are essential for achieving reliable, high-quality autonomous driving. This requires more reliable sensors and actuators, as there is always the potential that sensors and actuators will fail under real-world conditions. The sensitive condition-monitoring methods of sensors and actuators should be used to improve the reliability of the sensors and actuators. They should be able to detect and isolate the abnormal situations of faulty sensors and actuators. In this paper, a developed model-based method for condition monitoring of the sensors and actuators in an electric vehicle is presented that can determine whether a sensor has a fault and further reconfigure the sensor signal, as well as detect the abnormal behavior of the actuators with the reconfigured sensor signals. Through the simulation data obtained by the vehicle model in complex road conditions, it is proved that the method is effective for the state detection of sensors and actuators.


Assuntos
Condução de Veículo , Veículos Autônomos , Reprodutibilidade dos Testes , Simulação por Computador , Eletricidade
12.
Water Sci Technol ; 87(5): 1140-1158, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36919739

RESUMO

Iron oxyhydroxides for heavy metal treatment have attracted wide attention. In this work, iron oxyhydroxides of isomeric FeOOH (GpI) and tunnel-structural schwertmannite/akaganéite (GpII) were selected to study chromium (Cr(III)) adsorption removal from acidic aqueous solutions by batch experiments, under various reaction time, adsorbate/adsorbent level, pH and anions. Adsorption processes well fitted to pseudo-second-order kinetics (R2 = 0.992-0.999, except for 0.829 for Lep). Isotherm data could be fitted by Langmuir (R2 = 0.901-0.985), Freundlich (R2 = 0.884-0.985) and Temkin (R2 = 0.845-0.961) models at pH 3.7. Langmuir maximum adsorption capacities (mg/g) were 10.4-18.8 (FeOOH, except for 3.08 for Gth2) in GpI, and 20.60/43.40 (Sch-Chem/Sch-Bio) and 12.80/24.70 (Aka-Chem/Aka-Bio) in GpII. Adsorption capacities would gradually increase as Cr(III) concentrations increased within 0-40 mg/L, and could be markedly affected by the SO42- and H2PO4- anions. There were stable adsorption capacities at about pH 3.7, and then increased at pH 3.7-4.1. The Fourier transform infrared (FTIR) and X-ray photoelectron spectroscopy (XPS) results showed that adsorption mechanisms were electrostatic interaction and surface complexation. In addition, three optimal bio-/chem-schwertmannite and lepidocrocite adsorbents had good reusable properties and treating abilities of Cr(III)-polluted waters at pH 4.0. These results could provide a theoretical basis for the application of iron oxyhydroxides in removing Cr(III) from acid wastewaters.


Assuntos
Cromo , Poluentes Químicos da Água , Cromo/química , Adsorção , Poluentes Químicos da Água/química , Água/química , Ferro , Concentração de Íons de Hidrogênio , Cinética , Espectroscopia de Infravermelho com Transformada de Fourier , Soluções
13.
J Org Chem ; 87(23): 16019-16025, 2022 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-36377738

RESUMO

An efficient one-pot synthesis of 1,1'-biisoquinolines by a three-component reaction of commercially available raw materials (benzils, NH4OAc, and alkynes) is disclosed. This complicated reaction involves in situ diimine formation via benzil-NH4OAc condensation, Rh(III)-catalyzed 2-fold imine-directed C-H activation, and annulation with alkynes. Both symmetric and unsymmetric 1,1'-biisoquinolines could be assembled in moderate to high yields. The reaction mechanism is supported through ESI-MS, in which Cp*ClRh+, Cp*(OAc)Rh+, Cp*(OPiv)Rh+, and two rhodacycle intermediates are successfully detected to explain the evolution of rhodium species.

14.
Org Biomol Chem ; 20(19): 3913-3916, 2022 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-35507316

RESUMO

A palladium-catalyzed decarbonylative/decarboxylative [4 + 2] annulation of phthalic anhydrides with cyclic diaryliodonium salts to synthesize triphenylenes has been developed. The reaction shows broad substrate scope with a high yield of up to 99%, and it provides an efficient and fast way to access functionalized triphenylenes in only one hour.

15.
Mikrochim Acta ; 189(2): 68, 2022 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-35064830

RESUMO

A good water-soluble and stable nanocomposite has been facilely prepared by the encapsulation of CsPbBr3 QDs via cetyltrimethylammonium bromide and mineral oil through sonication, namely CsPbBr3@CMO nanocomposite. Such method is very quick and simple without complicated instruments and strict conditions. The results reveal that the synthesized CsPbBr3@CMO nanocomposite is spherical with uniform size and shows remarkably good solubility and stability in water. Specifically, the fluorescent intensity of CsPbBr3@CMO nanocomposite in water is decreased by 0.76% after 3 h; this result is comparable with those in earlier studies, and the good stability in water might be owned to the hydrophobic core of the CsPbBr3@CMO nanocomposite. The prepared CsPbBr3@CMO nanocomposite has been applied as a sensitive fluorescent probe for monitoring hydrogen sulfide (H2S), and the fluorescence intensity (~ 524 nm) has a linear relationship with the concentration of H2S in the range 0.15-105 µM with a detection limit of 53 nM, demonstrating application for monitoring H2S in rat brain coupled with microdialysis apparatus with satisfied results. The present study not only provides a simple but sensitive approach for the detection of H2S in living body, but also paves the way for expanding the application of CsPbBr3 QDs to aqueous medium.

16.
Int J Mol Sci ; 23(23)2022 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-36499119

RESUMO

Plagiomnium acutum T. Kop. (P. acutum) has been used as a traditional Chinese medicine for thousands of years to treat cancer but lacks evidence. The objective of this work was to reveal the chemical composition of P. acutum essential oil (PEO) and explore its potential antitumor activity and molecular mechanism. PEO was prepared by the simultaneous distillation-extraction method and characterized by gas chromatography/mass spectroscopy. CCK8 assay, flow cytometry, western blot, and immunofluorescence techniques were used to analyze the effects and mechanism of PEO against cancer cells. A total of 74 constituents of PEO were identified, with diterpenes (26.5%), sesquiterpenes (23.89%), and alcohols (21.81%) being the major constituents. Two terpenoids, selina-6-en-4-ol and dolabella-3,7-dien-18-ol, were detected in PEO for the first time. PEO showed significant cell growth inhibitory activity on HepG2 and A549 cells by blocking the G1 phase and inducing apoptosis, which may be attributed to its upregulation of p21Cip1 and p27Kip1 proteins and interference with mitochondrial membrane potential effect. Dolabella-3,7-dien-18-ol accounts for 25.5% of PEO and is one of the main active components of PEO, with IC50 values in HepG2 and A549 cells of (25.820 ± 0.216) µg/mL and (23.597 ± 1.207) µg/mL, respectively. These results confirmed the antitumor medicinal value of P. acutum and showed great application potential in the pharmaceutical industry.


Assuntos
Antineoplásicos Fitogênicos , Bryopsida , Óleos Voláteis , Sesquiterpenos , Humanos , Células A549 , Apoptose , Proliferação de Células , Inibidor de Quinase Dependente de Ciclina p27 , Óleos Voláteis/farmacologia , Óleos Voláteis/química , Sesquiterpenos/farmacologia , Sesquiterpenos/química , Bryopsida/química , Células Hep G2 , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia
17.
J Sci Food Agric ; 101(13): 5520-5528, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33719065

RESUMO

BACKGROUND: A one-off application of combining controlled-release urea (CRU) and conventional urea has been recommended for the reduction of nitrogen (N) loss and improvement of grain yield. However, the effects of combining CRU and urea with different surface mulching has not been studied in detail, and the underlying agronomical and physiological mechanisms need to be more clearly understood. RESULT: A 3-year field study was conducted to determine the effects of combining CRU and urea with different surface mulching on dry matter, N accumulation and translocation, nitrate nitrogen (NO3 - -N) residuals and loss in maize grown under rain-fed conditions. Three surface mulching [plastic film mulching (FM), straw mulching (SM) and no mulching (NM)] as well as three N fertilization [combining CRU and urea with 1:2 as the baseline application (NC), a split urea application with 4:3:3 (NU) and a N control (N0)] were used. The FM under NC fertilization increased N uptake, decreased NO3 - -N residual in the deep soil layer, and decreased N loss. The FM, SM and NM under NC fertilization increased 3-year mean grain yields by 5.8%, 4.0% and 4.6%, respectively, compared to that under NU fertilization. The FM under NC fertilization showed the highest grain yield and economic return. CONCLUSION: Properly managing N application by mixing CRU and urea in a one-off application combined with plastic film mulching may have the potential to provide a better compromise among grain yield, N loss and economic returns for maize in rain-fed farmland. © 2021 Society of Chemical Industry.


Assuntos
Produção Agrícola/métodos , Preparações de Ação Retardada/metabolismo , Ureia/metabolismo , Zea mays/crescimento & desenvolvimento , Zea mays/metabolismo , Produção Agrícola/instrumentação , Preparações de Ação Retardada/análise , Fertilizantes/análise , Chuva , Solo/química , Ureia/análise , Água/análise , Água/metabolismo
18.
Opt Express ; 28(10): 15601-15610, 2020 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-32403584

RESUMO

Manipulating circularly polarized (CP) light waves at will are highly important for photonic researches and applications. Recently, while Pancharatnam-Berry (PB) metasurfaces have shown unprecedented capabilities to control CP light, meta-devices constructed so far always suffer from the limitations of low-efficiency and narrow bandwidth. Here, we propose a scheme to construct PB metasurfaces with these two issues well addressed. To verify our idea, two PB meta-devices are designed and fabricated for achieving high-efficiency and broadband photonic spin Hall effect and focusing effect, respectively. Experimental results, in good agreement with full wave simulations, demonstrate the desired functionalities with efficiencies reaching 80% within an ultra-wide frequency band (8.2-17.3GHz). The proposed design scheme is generic and can be extended to high-frequency regimes. Our work can stimulate the realizations of high-performance and broadband PB meta-devices with diversified functionalities.

19.
Org Biomol Chem ; 18(43): 8810-8826, 2020 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-33112319

RESUMO

Organic ionic compounds, especially those with organic cations, are commonly applied in ionic liquids (ILs), organocatalysts, (a)NHC ligands, ion recognition, and optoelectronic materials. The direct C-H functionalization of organic cations offers valuable opportunities for the rapid assembly of diverse functionalized cations and for their further exploitation in material science applications. This review summarizes the substantial progress that has been made in the C-H functionalization of organic cations from the 1960s to May 2020, including transition metal-mediated/catalyzed C-H alkylation, arylation, and annulation, and photo-induced C-H functionalization. Substrate scopes, limitations, regio-/chemoselectivity, and reaction mechanisms are discussed. In addition, the applications of some new organic functional materials are briefly exemplified. This review also aims to serve as a reminder that much care should be taken when using organic ionic compounds as solvents, because they can behave as reactants that can break up desired coupling reactions.

20.
Org Biomol Chem ; 18(25): 4824-4830, 2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-32608470

RESUMO

Dihydrocinnolines have significant pharmacological properties. Herein, we investigate a Cu-catalyzed tandem N-arylation reaction of phthalhydrazides with cyclic iodonium salts to construct dihydrobenzo[c]cinnoline derivatives. Various iodonium salts, such as symmetrical, unsymmetrical, aryl-aryl, and aryl-heteroaryl ones, could react with phthalhydrazides smoothly and give the title products in moderate to high yields. Moreover, the -NH2 group, which has been diarylated by cyclic iodonium salts to form carbazoles in previous reports, is also well tolerated in this work.

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