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1.
Science ; 384(6693): 301-306, 2024 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-38635711

RESUMEN

China's massive wave of urbanization may be threatened by land subsidence. Using a spaceborne synthetic aperture radar interferometry technique, we provided a systematic assessment of land subsidence in all of China's major cities from 2015 to 2022. Of the examined urban lands, 45% are subsiding faster than 3 millimeters per year, and 16% are subsiding faster than 10 millimeters per year, affecting 29 and 7% of the urban population, respectively. The subsidence appears to be associated with a range of factors such as groundwater withdrawal and the weight of buildings. By 2120, 22 to 26% of China's coastal lands will have a relative elevation lower than sea level, hosting 9 to 11% of the coastal population, because of the combined effect of city subsidence and sea-level rise. Our results underscore the necessity of enhancing protective measures to mitigate potential damages from subsidence.

2.
ACS Appl Mater Interfaces ; 15(30): 37093-37106, 2023 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-37488063

RESUMEN

Various strategies have been developed to improve the applicability of hydrophobic pesticides for better effectiveness in agriculture. However, existing formulations of hydrophobic pesticides still suffer from complicated processing, abused organic solvents, indispensable surfactants, or inescapable ecotoxicity, which strictly limit their applications. Herein, a dynamic covalent bond tailored pesticide (fipronil) amphiphile is constructed to address the above issues, which accomplishes the nanodispersion, full wetting, and precise delivery without organic solvents, surfactants, and materials simultaneously. By introducing a hydrophilic ligand on the hydrophobic fipronil through an imine bond, the cleavable fipronil amphiphile (FPP) exhibits superior water solubility and can even self-assemble into micelles at higher concentrations, which can be directly applied in powder form without organic solvents. Attributed to the suitable hydrophilic/hydrophobic ratio, FPP achieves full wetting and effective deposition on superhydrophobic rice leaves without surfactants. Moreover, benefiting from the unique dynamic nature of the imine bond, FPP maintains good storage stability while sensitively releasing back to fipronil under the humidity and pH trigger, consequently implementing the precise delivery for nontarget Apis cerana and target Chilo suppressalis without materials. To our knowledge, this dynamic covalent bond tailored amphiphile strategy is the first idea that simultaneously takes the dispersibility, wettability, and responsiveness of hydrophobic pesticides into account, providing a possibility to control the entire journey of field application and even promising to be incorporated into the synthesis process, thus paving the way for modern sustainable agriculture.

3.
Pest Manag Sci ; 79(7): 2603-2610, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36883550

RESUMEN

BACKGROUND: Neonicotinoids are among the most essential chemical insecticides worldwide because of their high activity against many important pests and wide application. However, their application is limited by their toxicity to honeybees. Therefore, the development of a facile route to fabricate efficient and eco-friendly pesticide formulations is of great significance. RESULTS: In this study, clothianidin-loaded zeolitic imidazolate framework-8 (CLO@ZIF-8) nanoparticles were fabricated by a facile one-pot route using zinc nitrate as a Zn2+ source and characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, thermogravimetric analysis, energy-dispersive spectrometry and Fourier transform infrared spectroscopy. Based on the pH response of ZIF-8, a 'burst release effect' was observed for CLO@ZIF-8 at pH 3 and 5 within 12 h, in contrast to the slow and sustainable release at pH 8. CLO@ZIF-8 improved the retention ability of the pesticide liquid and remained 70% control efficacy on Nilaparvata lugens after water rinsed of sprayed CLO@ZIF-8. The pH response of CLO@ZIF-8 allowed it to maintain 43% control efficacy against N. lugens after 10 days of application, which was twice the efficacy of clothianidin solution (SCA). Moreover, CLO@ZIF-8 reduced the acute toxicity to honeybees (Apis mellifera) by ≥120-fold compared with SCA. CONCLUSION: This study provides new insights into the application of ZIF-8 to neonicotinoids and suggests the need for the development of a biocompatible and eco-friendly pesticide formulation. © 2023 Society of Chemical Industry.


Asunto(s)
Insecticidas , Zeolitas , Animales , Abejas , Neonicotinoides , Guanidinas , Tiazoles , Zeolitas/química
4.
Macromol Biosci ; 23(5): e2200577, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36758541

RESUMEN

Traumatic brain injury (TBI), a major public health problem accompanied with numerous complications, usually leads to serve disability and huge financial burden. The adverse and unfavorable pathological environment triggers a series of secondary injuries, resulting in serious loss of nerve function and huge obstacle of endogenous nerve regeneration. With the advances in adaptive tissue regeneration biomaterials, regulation of detrimental microenvironment to reduce the secondary injury and to promote the neurogenesis becomes possible. The adaptive biomaterials could respond and regulate biochemical, cellular, and physiological events in the secondary injury, including excitotoxicity, oxidative stress, and neuroinflammation, to rebuild circumstances suitable for regeneration. In this review, the development of pathology after TBI is discussed, followed by the introduction of adaptive biomaterials based on various pathological characteristics. The adaptive biomaterials carried with neurotrophic factors and stem cells for TBI treatment are then summarized. Finally, the current drawbacks and future perspective of biomaterials for TBI treatment are suggested.


Asunto(s)
Materiales Biocompatibles , Lesiones Traumáticas del Encéfalo , Humanos , Materiales Biocompatibles/farmacología , Materiales Biocompatibles/uso terapéutico , Lesiones Traumáticas del Encéfalo/terapia , Lesiones Traumáticas del Encéfalo/complicaciones , Regeneración Nerviosa , Neurogénesis , Células Madre
5.
ACS Appl Mater Interfaces ; 14(49): 55062-55074, 2022 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-36472305

RESUMEN

Hydrogels have been extensively used in agriculture to improve crop yields for their excellent properties. However, they are currently used either as pesticide delivery platforms or water retention agents alone; the combination of these two functions into one agricultural hydrogel formulation has never been reported, which is crucial to promote sustainable development in agriculture. Herein, using poly(ß-cyclodextrin) and adamantane-grafted poly(acrylic acid) (PAA-Ada) as the host and guest, respectively, an easy operating, multi-responsive, and safer hydrogel delivery system for insecticides is fabricated by the host-guest interaction between cyclodextrin and adamantane, which can load uniformly dispersed insecticides (fipronil, imidacloprid, and thiamethoxam) up to 60%. Benefiting from the carboxyl and hydroxyl groups on polymer chains, different temperatures (25, 35, and 45 °C) and pH values (5.0, 6.8, and 10.0) change the intermolecular forces within the hydrogel network and then the diffusion of the content, finally resulting in controlled release behaviors. Besides, this platform can rapidly release the insecticides in the presence of amyloglucosidase due to its ring-opening effect on cyclodextrin. Moreover, this platform exhibits high water-retaining capacity toward soil, which can increase the maximum water absorption of nutrient soil and quartz sand by 31.6 and 13.9%, respectively, and slows down the water loss. Compared with commercial formulation, this smart system reduces the acute toxicity to non-target organism earthworms by 52.4% and improves the efficacy against target organism aphids by 47.3%, showing better durability, lower environmental toxicity, and higher efficiency. To our knowledge, this is the first idea that simultaneously adopts the water-retaining capacity and controlled release ability of hydrogels to improve insecticide efficacy. In this regard, this smart hydrogel platform holds great potentials as slow-release granules with water-holding ability for protection against insect pests, providing an alternative platform for the sustainable development in green agriculture.


Asunto(s)
Adamantano , Ciclodextrinas , Insecticidas , Agua/química , Preparaciones de Acción Retardada , Suelo/química , Hidrogeles/química , Control de Plagas
6.
Sci Total Environ ; 851(Pt 1): 158169, 2022 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-35995160

RESUMEN

Low pesticide efficiency has caused serious environmental pollution and economic loss, which are closely related to each link in the targeted delivery of pesticides. However, the existing strategies for improving pesticide utilization rate are not comprehensive, and the regulation of foliar absorption and biological activity has been neglected. As surfactants are the most important agricultural synergists, the impact, wetting, adhesion, and leaf retention behaviors of pyraclostrobin (PYR) droplets containing the surfactant Triton X (TX) series on hydrophobic scallion leaf surfaces were studied. The results showed that TX-102 can sufficiently reduce the splash and roll of droplets when they impact inclined leaves, owing to its low dynamic surface tension. Moderate wetting ability and high adhesion also maximizes leaf retention of the TX-102-added PYR solution sprayed on scallion leaves. Furthermore, TX-102 improved the permeation and absorption of PYR in scallion leaves through the synergistic effects of opening the stomata and dissolving the waxy layer. The synergistic bioactivity of TX-102 against pathogenic fungi Alternaria porri and its safety to non-target organism zebrafish have also been demonstrated. Our study provides a more comprehensive theoretical rationale for screening adjuvants to improve the effectiveness and bioavailability of pesticides and reduce the risk of pesticides entering the environment.


Asunto(s)
Plaguicidas , Tensoactivos , Animales , Disponibilidad Biológica , Octoxinol , Plaguicidas/análisis , Estrobilurinas , Tensoactivos/química , Humectabilidad , Pez Cebra
7.
J Colloid Interface Sci ; 584: 92-102, 2021 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-33069032

RESUMEN

As the applications of supramolecular assemblies are ultimately inscribed in their nanostructures, strategies that can precisely fabricate and regulate supramolecular architectures from small molecules are of great importance. Herein, in this research multiple modulations of supramolecular assembled structures of a natural triterpenoid-tailored bipyridinium amphiphile, 1-[2-(methyl glycyrrhetate)-2-oxoethyl]-[4,4']bipyridinium bromide (MGBP), have been achieved by adjusting solvents or counterions. Depending on the polarity of solvents, MGBP assembled into nanofibers, helices, pentagon and hexagon microsheets, respectively. Moreover, the nanofibers in methanol/water can transform into ribbons, robust fibers and fiber bundles by addition of counterions with different ionic sizes and valences. This work presents a simple and feasible methodology to modulate assembly structures of a natural triterpenoid-based amphiphile, which may expand the application of natural products in supramolecular materials.

8.
ACS Appl Mater Interfaces ; 12(44): 50126-50134, 2020 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-33090773

RESUMEN

Despite small-molecule surfactants and polymers being widely used as pesticide adjuvants to inhibit droplet bouncing and splashing, they still have intrinsic drawbacks either in the easy wind drift and evaporation, the unfavorable wettability, or the usage of nonrenewable resources. In this paper, we found that upon droplet impacting, 1D nanofibers assembled from natural glycyrrhizic acid (GL) could pin on the rough hydrophobic surface and delay the retraction rate of droplets effectively. Using GL as a tank-mixed adjuvant, the efficiency of glyphosate to control the weed growth was improved significantly in the field experiment, which addressed the dilemmas of current adjuvants elegantly. Our work not only provides a constructive way to overcome droplet bouncing but also prompted us to verify in future if all 1D nanofibers assembled from different small molecules can display similar control efficiencies.


Asunto(s)
Glicina/análogos & derivados , Ácido Glicirrínico/farmacología , Hojas de la Planta/química , Setaria (Planta)/efectos de los fármacos , Glicina/química , Glicina/farmacología , Ácido Glicirrínico/química , Interacciones Hidrofóbicas e Hidrofílicas , Estructura Molecular , Nanofibras/química , Tamaño de la Partícula , Setaria (Planta)/crecimiento & desarrollo , Propiedades de Superficie , Glifosato
9.
J Colloid Interface Sci ; 541: 93-100, 2019 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-30684754

RESUMEN

Even though amphiphilic natural products have been widely employed in cosmetics, food, and pesticide formulations, the development of a compound with stimuli-responsiveness is still highly significant. Inspired by the low cost, biocompatibility, pH resistance and amphiphilicity of natural glycyrrhizic acid (Gly), we designed and synthesized an amphiphilic homopolymer, namely, poly(glycyrrhizic acid) (PGly), via reversible addition-fragmentation chain transfer (RAFT) polymerization. The two carboxylic groups on the side chain of PGly promoted it as a multiple pH-responsive polymeric surfactant. As the pH was decreased from 5.0 to 2.0, the PGly transformed from the extension to the coil state and further aggregated into nano/micro particles. During this process, the surface charge, surfactivity and diffusion rate of PGly decreased along with the decreasing pH. Moreover, with ultrasonic treatment (UT), the aggregates that formed at lower pH values decreased (pH 3.0 and 2.0) or almost disappeared (pH 4.0), indicating that these insoluble aggregates at lower pH were broken by UT and were then reassembled into the compacted PGly nanoparticles. Based on the above results, the emulsion (20 wt% xylene) stabilized by 0.1 wt% PGly was fabricated using ultrasonic emulsification for which the diameter distribution and the dispersion state can be reversibly regulated by pH (2.0-5.0). This natural polymeric surfactant exhibited a favorable surfactivity and multiple pH responsiveness in the preparation of emulsions, showing its potential for application in the controlled release of pesticide formulations and in the recovery of organic pollution.


Asunto(s)
Ácido Glicirrínico/química , Nanopartículas/química , Plaguicidas/química , Polímeros/química , Tensoactivos/química , Composición de Medicamentos , Emulsiones , Concentración de Iones de Hidrógeno , Polimerizacion
10.
Pestic Biochem Physiol ; 100(2): 172-181, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21760647

RESUMEN

A previous study demonstrated that the flight capacity of Nilaparvata lugens adults treated with triazophos was enhanced significantly. However, the physiological and regulative mechanisms of the flight enhancement are not well understood. Trehalose is a primary blood sugar in insects, and the enzyme trehalase is involved in energy metabolism. The present study investigated the effects of triazophos on the trehalose content, trehalase activity (soluble trehalase and membrane-bound trehalase) and the mRNA transcript levels of their corresponding genes (NlTre-1 and NlTre-2) in fifth instar nymphs, as well as in the brachypterous and macropterous N. lugens adult females. Our findings showed that the trehalose content in fifth instar nymphs as well as in the brachypterous and the macropterous adults significantly decreased following triazophos treatment. However, the glucose content, soluble trehalase activity and expression level of NlTre-1 mRNA increased significantly compared to the controls. No significant enhancement of NlTre-2 expression was found, indicating that regulation of energy metabolism of triazophos-induced flight capacity in N. lugens was not associated with NlTre-2 expression. In addition, soluble trehalase activity and the expression level of NlTre-1 mRNA in the macropterous females was significantly higher than that in the brachypterous females. The present findings provide valuable information on the molecular and regulative mechanisms of the increased flight capacity found in adult N. lugens after treatment with triazophos.

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