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Vegetation serves as a crucial indicator of ecological environment and plays a vital role in preserving ecosystem stability. However, as urbanization escalates rapidly, natural vegetation landscapes are undergoing continuous transformation. Paradoxically, vegetation is pivotal in mitigating the ecological and environmental challenges posed by urban sprawl. The middle and lower Yangtze River Basin (MLYRB) in China, particularly its economically thriving lower reaches, has witnessed a surge in urbanization. Consequently, this study explored the spatiotemporal variations of normalized difference vegetation index (NDVI) in the MLYRB, with an emphasis on elucidating the impact of climate change and urbanization on vegetation dynamics. The results indicate that a significant increasing trend in NDVI across the MLYRB from 2000 to 2020, a pattern that is expected to persist. An improvement in vegetation was observed in 94.12% of the prefecture-level cities in the study area, predominantly in the western and southern regions. Temperature and wind speed stand out as dominant contributors to this improvement. Nevertheless, significant vegetation degradation was detected in some highly urbanized cities in the central and eastern parts of the study area, mainly attributed to the negative effects of escalating urbanization. Interestingly, a positive correlation between NDVI and the urbanization rate was observed, which may be largely related to proactive ecological preservation policies. Additionally, global climatic oscillations were identified as a key force driving periodic NDVI variations. These findings hold significant importance in promoting harmonious urbanization and ecological preservation, thereby providing invaluable insights for future urban ecological planning efforts. [ABSTRACT FROM AUTHOR]

Vegetation plays a crucial role in nature, with intricate interactions between it and the geographical environment. The Yangtze River Basin (YRB) refers to the third largest river basin globally and an essential ecological security barrier in China. Monitoring vegetation dynamics in the basin is of profound significance for addressing climate change, soil erosion, and biodiversity loss in the basin's ecosystems. Here, we investigate the spatiotemporal variations of vegetation at both the basin and land cover scales in the YRB from 2000 to 2020. We elucidate the determinants driving the changes and explore future normalized difference vegetation index (NDVI) trends. The results indicate that NDVI in the YRB increased at a rate of 0.0032 year−1 (p < 0.01) over the past 21 years, and it is anticipated to maintain an upward trend in the future. Regions in the upper and middle reaches of the YRB demonstrated higher NDVI, whereas regions in the headwater area and the lower reaches showed lower NDVI. Significant vegetation improvement was primarily concentrated in the central part of the basin, while noticeable vegetation degradation was observed in the eastern region. Temperature and wind speed were identified as the primary controlling factors affecting vegetation greenness. Global‐scale climate oscillations played a significant role in driving periodic variations in NDVI, with La Niña events tending to increase NDVI, while El Niño events hindered its rise. Land cover types were influenced by long‐term interactions between natural factors and human activities, although short‐term vegetation variations might be more affected by the latter. Our findings provide valuable insights into the mechanisms behind vegetation variability driven by multiple variables, and the strong vegetation carbon sink capacity advances the conservation and development of ecosystems. [ABSTRACT FROM AUTHOR]

Importance: Recurrent respiratory tract infection (RRTI) is common in children. Inappropriate RRTI treatment will lead to asthma and other diseases, thereby seriously affecting the growth and physical health of children. Immune function modulation can prevent and alleviate childhood RRTI. Yupingfeng (YPF), a patented traditional Chinese medicine (TCM), has immunomodulatory effects and is widely used in China to treat children with RRTI. Objective: To evaluate the safety and efficacy of YPF monotherapy in treating children with RRTI. Methods: This multicenter, randomized, double‐blind, double‐simulation, noninferiority clinical trial was conducted from January 2015 to August 2017, with an 8‐week treatment period and 52‐week follow‐up after the drug withdrawal. Children aged 2–6 years with RRTI meeting the inclusion and exclusion criteria were enrolled in 13 hospitals in China and divided randomly into three groups (2:2:1 ratio) to receive YPF, pidotimod, or placebo. The primary outcome was the proportion of RRTI returning to normal standard level during the follow‐up. The secondary outcomes were reduction in the number of RRTI recurrences, effect on clinical symptoms (in accord with TCM practice), effect per symptom, and safety. The trial was registered at the Chinese Clinical Trials Registry (www.chictr.org.cn) under the unique identifier ChiCTR‐IPR‐15006847. Results: Three hundred and fifty‐one children were enrolled and randomly assigned to 3 groups; 124, 125, and 61 children in the YPF, pidotimod, and placebo groups, respectively, had completed the trial. During the follow‐up, the proportion of RRTI returning to normal standard level was 73.13%, 67.15%, and 38.81% with YPF, pidotimod, and placebo, respectively (P < 0.0001). The proportion of cases who returned to normal standard level in the YPF group was 34.32% higher than that in the placebo group. The safety profile did not significantly differ among the groups. Interpretation: YPF granules were noninferior to the active control drug pidotimod oral solution for the treatment of RRTI in children, and were superior to placebo, with a high safety profile. [ABSTRACT FROM AUTHOR]

As one of the important thiazole derivatives, 2-aminobenzothiazole (2-ABT) has been widely used as a structural unit in the synthesis of anti-oxidants, anti-inflammatories, herbicides, antibiotics, and thermoplastic polymers. In this study, the interaction of 2-ABT with human serum albumin (HSA) was investigated in vitro under simulated physiological conditions, using multi-spectroscopic techniques and a molecular modeling study. The binding constant and binding sites were determined through fluorescence quenching spectra. The site-competitive replacement experiments revealed that the precise binding site of 2-ABT on HSA was site II (subdomain IIIA). Moreover, molecular docking results illustrated the electrostatic interaction between Glu 450 and 2-ABT, in accordance with the conclusions from the calculated thermodynamic parameters and the effect of ionic strength. The effect of 2-ABT on the conformational changes of HSA were evaluated by ultraviolet-visible (UV-Vis) absorption, three-dimensional (3D) fluorescence, synchronous fluorescence, and circular dichroism (CD) spectroscopy. This work facilitates comprehensive understanding of the binding of 2-ABT with HSA, contributing to evaluate the molecular transportation mechanism and biotoxicity of 2-aminobenzothiazole derivatives in vivo.

Ciprofloxacin (CPFX) and enrofloxacin (ENFX) are two of the most widely used fluoroquinolones (FQs) in human and veterinary medicines. Their occurrence in the environment has received much attention because of the potential adverse effects on humans and ecosystem functions. In this paper, we investigated the interaction mechanism between the two FQs and lysozyme by the spectroscopic and molecular docking methods. As shown by the fluorescence spectroscopy, additions of CPFX or ENFX effectively quenched the intrinsic fluorescence of lysozyme, which was attributed to the formation of a moderately strong complex. The enthalpy change (ΔH) and entropy change (ΔS) indicated that van der Waals forces and hydrogen bonds were the dominant intermolecular forces in the binding of two FQs to lysozyme. Furthermore, data obtained by UV-vis absorption, synchronous fluorescence and circular dichroism (CD) suggested that both CPFX and ENFX could lead to the conformational and some microenvironmental changes of lysozyme. Finally, the molecular docking illustrated that the two FQs had specific interactions with the residues of Trp62 and Trp63.

Scenedesmus obliquus growth inhibition test was carried out to assess the toxicity of soil contaminated by heavy metals. The results showed that the growth rate of Scenedesmus obliquus was positively related to the concentration of heavy metals added to soil, and it was decreased with the increasing concentration of heavy metals. Two parameters were chosen and the sensitivities were compared. It was found that the cell growth rate was more sensitive than OD growth rate. The orders of general detection limit by EC50 of different metals were Pb > Cu > Zn > Cd by using cell growth rate as the test index and Pb > Cu > Cd > Zn by using OD as the test index. This study also indicated that under the complex pollution condition, the toxicity of heavy metals in soil was stronger than that in the case of soil contaminated by single metal.