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Tectonic transition from the Tethys to Palaeo‐Pacific regimes occurred during the Mesozoic in the South China Block. But the switching time and palaeogeographic pattern are still controversial. The Late Triassic to Middle Jurassic Longhai and Sandu basins along the NNE‐striking Chaling–Chenzhou–Linwu Fault were selected for provenance analysis and palaeogeographic reconstruction. Detrital zircons of all six samples from the Lower and Middle Jurassic yield peak ages of 250 ~ 400 Ma, 407 ~ 497 Ma, 562 ~ 1,167, 1,603 ~ 2,170 Ma, and 2,270 ~ 2,800 Ma, revealing pre‐Triassic tectono‐thermal events occurred within or beyond the South China Block. Late Triassic (207 ~ 236 Ma) and Early Jurassic (186 ~ 198 Ma) detrital zircons are also preserved in the Lower and Middle Jurassic. Composition and content variations of zircon ages in the Longhai Basin imply Jurassic stratigraphic inversion, which was caused by Middle Jurassic top‐to‐the‐SE thrusting of the Chaling–Chenzhou–Linwu Fault. Cathodoluminescence images, Th/U ratios, and rare earth elements patterns show that almost all analyzed zircons are of magmatic origin. Y versus U/Yb and Nb/Yb versus U/Yb discrimination diagrams indicate that 250 ~ 400 Ma, 207 ~ 250 Ma, and 186 ~ 198 Ma detrital zircons are continental zircons derived from Late Palaeozoic, Triassic, and Early Jurassic continental arcs, respectively. Provenance analysis indicate that the Middle and Lower Jurassic in the Longhai Basin were derived from the Nanling tectonic belt to the south, whereas the Lower Jurassic in the Sandu Basin from the Wuyishan domain to the east. The source‐to‐sink systems indicate that an NNE‐striking watershed occurred during Early to Middle Jurassic and separated the Longhai and Sandu basins. Tectonic uplift of the NNE‐striking watershed resulted from by Late Triassic transpression along the Chaling–Chenzhou–Linwu Fault. Combining these with two‐stage tectonic deformation and granitoids in the South China Block, the Mesozoic tectonic transition from the Tethys regime to the Palaeo‐Pacific regime occurred during the Late Triassic. [ABSTRACT FROM AUTHOR]

At present, cancer is the first cause of death for humans, but early detection and treatment can help improve prognoses and reduce mortality. However, further development of carrier-assistant drug delivery systems (DDSs) is retarded by the aspects such as the low drug-carrying capacity, carrier-induced toxicity and immunogenicity, complex synthesis manipulation. The development of nanoscale drug delivery systems (NDDS) have been rapidly developed to address these issues. In this article, we used PLGA-PEG with good biocompatibility to encapsulate Fe3O4 nanoparticles (a magnetic resonance imaging contrast agent) and DOX (an antitumour drug) via the emulsion-solvent evaporation method, aimed at achieving a dual function of the early detection and the treatment of mammary cancer. The results showed that the Fe3O4/DOX/PLGA-PEG nanoparticles had a relatively uniform size, a high carrier rate of Fe3O4 and high encapsulation efficiency of DOX, and a relatively high activity of released DOX within 120 h. In addition, in vitro studies showed that the Fe3O4/DOX/PLGA-PEG nanoparticles were cytocompatibility in NIH 3T3 fibroblast cells culture study while had a special effect on destroying human breast cancer MCF-7 cells compared with pure DOX solution. In vitro studies revealed that the Fe3O4/DOX/PLGA-PEG enabled enhanced T2 contrast magnetic resonance. Overall, our multifunctional Fe3O4/DOX/PLGA-PEG nanoparticles, composed of biocompatible substances and therapeutic/imaging materials, have great potential for the early detection of cancer and accurate drug delivery via the dynamic monitoring using MRI. [ABSTRACT FROM AUTHOR]

With pot experiment and simulating field ecological environment, this paper studied the effects of different slow/ controlled release N fertilizers on the soil nitrate - reductase and urease activities and microbial biomass C and N at maize seedling stage. The results showed that granular urea amended with dicyandiamide (DCD) and N-(n-bultyl) thiophosphoric triamide (NBPT) induced the highest soil nitrate-reductase activity, granular urea brought about the highest soil urease activity and microbial biomass C and N, while starch acetate (SA)-coated granular urea, SA-coated granular urea amended with DCD, methyl methacrylate (MMA) -coated granular urea amended with DCD, and no N fertilization gave a higher soil urease activity. Soil microbial C and N had a similar variation trend after applying various kinds of test slow/controlled release N fertilizers, and were the lowest after applying SA-coated granular urea amended with DCD and NBPT. Coated granular urea amended with inhibitors had a stronger effect on soil biological activities than coated granular urea, and MMA-coating had a better effect than SA-coating.

The study showed that on a sheltered vegetable field, a long-term application of organic plus chemical fertilizers induced a higher content of loosely combined soil humus than applying chemical fertilizers alone, while there was no significant difference in firmly combined humus content among different fertilization treatments. More tightly combined humus was observed in organic fertilizer treatments than in chemical fertilizer treatments, and the highest content (11.53 g x kg(-1)) was in the treatment of organic fertilizer plus chemical NPK. The ratio of loosely/tightly combined humus tended to decrease after a long-term application of organic fertilizer, being the lowest (1.10) in the treatment of organic fertilizer plus chemical NPK.

This paper studied the dynamics of microbial biomass N in a black soil long-term fertilized with farmyard manure (M2 and M4) and chemical fertilizer (NPK) during crop growth season. The results showed that the soil microbial biomass N was 25.52-239.12 mg x kg(-1) in M4, 10.40-94.31 mg x kg(-1) in M2, 6.27-87.04 mg x kg(-1) in NPK, and 9.15-69.81 mg x kg(-1) in CK. In same treatment, the highest value was 7-14 times higher than the lowest value. Treatments NPK and M2 had the highest value of microbial biomass N at reproductive growth stage, while M4 and CK had it at vegetative growth stage. The significant difference of soil microbial biomass N caused by different treatments was not changed with plant growth stages. The dynamics of soil microbial biomass N had a significant correlation some soil biological, physical and chemical properties. A significant positive correlation was found between soil microbial biomass N and soil biological, physical and chemical properties, plant N, P and K contents, soil moisture, and grain crude protein.

This paper studied the microbial biomass P in a long-term fertilized black soil. The soil was fertilized by farmyard manure (M2, M4) and chemical fertilizer (NPK), and the dynamics of soil microbial biomass P was monitored during crop growth season. The results showed that the microbial biomass P in different treatments was 8.75-47.68 mg x kg(-1) (M4), 3.02-37.16 mg x kg(-1) (M2), 1.59-10.62 mg x kg(-1) (NPK), and 0.76-6.74 mg x kg(-1) (CK). The microbial biomass P in M4 and M2 was the highest at reproductive growth stage, and that in NPK and CK was the highest at early growth stage. The significant difference of soil microbial biomass P induced by different amounts and types of fertilizer application was not varied with the period and stage of plant growth. In all treatments, no significant correlation was found between the dynamics of soil microbial biomass P and the soil biological, physical and chemical properties in plant growth period. Soil microbial biomass P had a very significant positive correlation with soil biological, physical and chemical properties (expect K), and a significant positive correlation with the N, P and K contents of plants and soil water content.

The effect of long-term fertilization on the dynamics of microbial biomass C in a typical black soil of Northeastern China was studied in a field trail treated by different fertilizations. The results showed that the amount of soil microbial biomass C under different fertilizations varied significantly with growth stages. It was the highest in farmyard manure (M2 and M4) treatments, with a less seasonal fluctuation, second in NPK treatment, the peak at sowing period, and the lowest in CK, the peak at wax maturity stage. No significant correlation was found between the dynamic changes of soil microbial biomass C and soil biological, physical and chemical properties in all treatments, but the correlation of soil microbial biomass C with the contents of N, P and K in plants and that of crude protein in grain was significantly positive.