Phenylboronic acid-functionalized magnetic metal-organic framework nanoparticles for magnetic solid phase extraction of five benzoylurea insecticides.

This research involves the construction of a phenylboronic acid-functionalized magnetic UiO-66 metal-organic framework (MOF) nanoparticle (CPBA@UiO-66@Fe3O4). Its design is primarily for the magnetic solid phase extraction (MSPE) of benzoylurea insecticides. An organic ligand, 2-amino terephthalic acid (2-ATPA), facilitated the introduction of amino groups while keeping the original crystal structure of UiO-66 intact. The constructed UiO-66 MOF showcases a porous structure and extensive surface area, thereby providing an optimal platform for further functionalization. The employment of 4-carboxylphenylboronic acid as a modifier notably amplified the extraction efficiency for benzoylureas. This improvement was due to the formation of B-N coordination and other secondary interactions. By integrating this with high-performance liquid chromatography (HPLC), we established a quantitative analytical method for benzoylurea insecticides. This method achieved a wide linear range (2.5-500 µg L-1 or 5-500 µg L-1), satisfactory recoveries (83.3-95.1%), and acceptable limits of detection (LODs: 0.3-1.0 µg L-1). The developed method proved successful when applied to six tea infusion samples, representing China's six major tea categories. Semi-fermented and light-fermented tea samples demonstrated relatively higher spiking recoveries.

The Effect of Terbinafine and Its Ionic Salts on Certain Fungal Plant Pathogens.

Terbinafine, an inhibitor of squalene epoxidase in ergosterol biosynthesis, is chiefly utilized as an antifungal medication with potential uses in pesticide applications. This study explores the fungicidal efficacy of terbinafine against prevalent plant pathogens and confirms its effectiveness. To augment its water solubility, five ionic salts of terbinafine were synthesized by pairing them with organic acids. Among these salts, TIS 5 delivered the most impressive results, amplifying the water solubility of terbinafine by three orders of magnitude and lessening its surface tension to facilitate better dispersion during spraying. The in vivo experiments on cherry tomatoes showed that TIS 5 had a superior therapeutic activity compared to its parent compound and two commonly used broad-spectrum fungicides, pyraclostrobin and carbendazim. The results highlight the potential of terbinafine and its ionic salts, particularly TIS 5, for use as fungicides in agriculture due to their synergistic effects with furan-2-carboxylate.

Multi-terrane structure controls the contrasting lithospheric evolution beneath the western and central-eastern Tibetan plateau.

The Tibetan plateau is manifested by contrasting along-strike lithospheric structures, but its formation mechanism and the relationship with the heterogeneous multi-terrane configuration is a challenging problem. Here we conduct systematic numerical modeling to explore the roles of width, density, and rheological properties of the multiple terranes in the lithospheric evolution of the Tibetan plateau, which reveals two distinct collision modes. In Mode-I, the lithospheric mantles of both the strong and weak terranes in the Tibetan plate are completely detached, followed by the underthrusting of Indian lithosphere beneath the whole plateau. Alternatively, Mode-II is characterized by full detachment of the weak terranes, but (partial) residue of the strong terranes during collision. These two contrasting modes, broadly consistent with the lithospheric structures of western and central-eastern Tibetan plateau, respectively, are strongly dependent on the along-strike variation of the width of the strong Lhasa-Qiangtang terranes.

Depth variations of P-wave azimuthal anisotropy beneath Mainland China.

A high-resolution model of P-wave anisotropic tomography beneath Mainland China and surrounding regions is determined using a large number of arrival-time data recorded by the China seismic network, the International Seismological Centre (ISC) and temporary seismic arrays deployed on the Tibetan Plateau. Our results provide important new insights into the subducted Indian plate and mantle dynamics in East Asia. Our tomographic images show that the northern limit of the subducting Indian plate has reached the Jinsha River suture in eastern Tibet. A striking variation of P-wave azimuthal anisotropy is revealed in the Indian lithosphere: the fast velocity direction (FVD) is NE-SW beneath the Indian continent, whereas the FVD is arc parallel beneath the Himalaya and Tibetan Plateau, which may reflect re-orientation of minerals due to lithospheric extension, in response to the India-Eurasia collision. There are multiple anisotropic layers with variable FVDs in some parts of the Tibetan Plateau, which may be the cause of the dominant null splitting measurements in these regions. A circular pattern of FVDs is revealed around the Philippine Sea slab beneath SE China, which reflects asthenospheric strain caused by toroidal mantle flow around the edge of the subducting slab.

Stochastic dynamic model of SARS spreading.

Based upon the simulation of the stochastic process of infection, onset and spreading of each SARS patient, a system dynamic model of SRAS spreading is constructed. Data from Vietnam is taken as an example for Monte Carlo test. The preliminary results indicate that the time-dependent infection rate is the most inportant control factor for SARS spreading. The model can be applied to prediction of the course with fluctuations of the epidemics, if the previous history of the epidemics and the future infection rate under control measures are known.