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Carboxylesterase (CE) is crucial in metabolizing ester-containing biomolecules and is particularly significant in liver metabolic diseases. Herein, we present the first activatable NIRF/PA dual-mode imaging probe QHD-CE for detection of CE in vitro and in vivo. QHD-CE displays excellent sensitivity and selectivity for CE with a high reaction efficiency (∼90 min). By utilizing QHD-CE, the dynamic changes of CE in drug-induced liver injury and diabetic mice models were monitored. [ABSTRACT FROM AUTHOR]

Nanoparticles (NPs) have been widely used in agriculture, and lanthanum oxide nanoparticles (La2O3) NPs can regulate plant growth. La2O3 NPs treatment was hypothesized to affect the accumulation and distribution of substances in rice seedlings under wet and dry nursery conditions. The objective of the present study was to ascertain the effects of La2O3 NPs foliar spray on the morphology and physiology of fragrant rice seedlings under wet and dry nursery conditions. Seedlings of two fragrant rice cultivars, namely 'Xiangyaxiangzhan' and 'Yuxiangyouzhan,' were grown under wet and dry nursery conditions with La2O3 NPs treatments at three concentrations (CK, La2O3 NPs 0 mg L−1; T1, La2O3 NPs 20 mg L−1; and T2, La2O3 NPs 40 mg L−1). The results showed that the seedling-raising method was significantly associated with La2O3 NPs application (P < 0.05), affecting the leaf area of both cultivars. Changes in plant morphological parameters, such as dry weight and root–shoot ratio, were the reasons for the differences in cultivars in response to La2O3 NPs application. Changes were also observed in the plant morphological and physiological parameters of leaf area, specific leaf area, chlorophyll contents, antioxidant properties, and activities of nitrogen metabolism enzymes. The relationship between morphological and physiological processes in fragrant rice was investigated to test the hypothesis. In both wet and dry nursery methods, the T2 concentration of La2O3 NPs was beneficial for rice seedlings and significantly increased their leaf area due to changes in morphological and physiological parameters. Therefore, the results of this study provide a theoretical basis for expanding the research on La2O3 NPs application in rice, as well as relevant references for strengthening rice seedlings in the nursery, which has a positive effect on the grain yield improvement in fragrant rice. [ABSTRACT FROM AUTHOR]

Using an iterative rain‐cell tracking method to identify and track mesoscale convective system (MCS) precipitation during the warm seasons (May–October) of 2015–2020, we reveal the seasonal variation in the spatiotemporal distribution, rainfall characteristics, and the life cycle of MCS precipitation in different months over North China. Notable MCS precipitation centers are located around mountain slopes and downstream areas. The diurnal peak of MCS rainfall is manifested as a southeastern delay from afternoon in mountainous regions to midnight or morning over downstream plains. In May and June, MCS rainfall is distributed on the hillside of Taihang–Yan mountains and the Shandong Peninsula. MCS precipitation gets an early evening peak on mountain slopes and a nocturnal maximum over the North China Plain (NCP). In July and August, the MCS activities extend to NCP, and another MCS precipitation center exists over the Luliang Mountains in western North China, under the seasonal march of the monsoon flow. The local diurnal peaks to the east of 114°E are generally later than in May and June, and MCS precipitation gets a peak during midnight to early morning over the NCP. MCSs in July and August feature the strongest intensity. In September and October, the MCS precipitation shifts to high terrain of the Taihang Mountains and its west, with an early afternoon peak. MCSs have the largest size and the fastest propagation speed in September and October, but with the weakest intensity. Compared with short‐lived MCSs, long‐lived MCSs have stronger precipitation intensity, larger rainfall area, and faster propagation speed. In addition, the life cycle of long‐lived MCS precipitation represents asymmetric development and decay. Long‐lived MCSs occur with more pronounced upper troposphere warming and low‐level anomalous southwesterlies. Meanwhile, higher specific humidity in the low‐ and mid‐level troposphere provides a more favorable environment for the maintenance of MCS precipitation. [ABSTRACT FROM AUTHOR]

The accuracy and reliability of satellite precipitation products (SPPs) are important for their applications. In this study, four recently presented SPPs, namely, GSMaP_Gauge, GSMaP_NRT, IMERG, and MSWEP, were evaluated against daily observations from 2344 gauges of mainland China from 2001 to 2018. Bivariate Moran's I (BMI), a method that has demonstrated high applicability in characterizing spatial correlation and dependence, was first used in research to assess their spatial correlations with gauge observations. Results from four conventional indices indicate that MSWEP exhibited the best performance, with a correlation coefficient of 0.78, an absolute deviation of 1.6, a relative bias of −5%, and a root mean square error of 5. Six precipitation indices were selected to further evaluate the spatial correlation between the SPPs and gauge observations. MSWEP demonstrated the best spatial correlation in annual total precipitation, annual precipitation days, continuous wet days, continuous dry days, and very wet day precipitation with global BMI of 0.95, 0.78, 0.78, 0.78, and 0.87, respectively. Meanwhile, IMERG showed superiority in terms of maximum daily precipitation with a global BMI value of 0.91. IMERG also exhibited superior performance in quantifying the annual count days that experience precipitation events exceeding 25 mm and 50 mm, with a global BMI of 0.96, 0.92. In four sub-regions, these products exhibited significant regional characteristics. MSWEP demonstrated the highest spatial correlation with gauge observations in terms of total and persistent indices in the four sub-regions, while IMERG had the highest global BMI for extreme indices. In general, global BMI can quantitatively compare the spatial correlation between SPPs and gauge observations. The Local Indicator of Spatial Association (LISA) cluster map provides clear visual representation of areas that are significantly overestimated or underestimated. These advantages make BMI a suitable method for SPPs assessment. [ABSTRACT FROM AUTHOR]

The accurate estimation of urban extreme precipitation is essential for urban design and risk management, which is hard for developing countries, due to the fast urbanization and sparse rain gauges. Satellite precipitation products (SPPs) have emerged as a promising solution. Not only near real-time SPPs can provide critical information for decision making, but post-processed SPPs can also offer essential information for climate change adaption, risk management strategy development, and related fields. However, their ability in urban extreme precipitation estimation has not been examined in detail. This study presents a comprehensive evaluation of four recent SPPs that are post-processed, including IMERG, GSMaP_Gauge, MSWEP, and CMFD, for their ability to capture urban extreme precipitation in mainland China at the national, city, and inner-city scales. The performance of the four SPPs was assessed using daily observations from the 821 urban gauges from 2001 to 2018. The assessment includes: (1) the extreme precipitation estimates from the four SPPs in the total urbanized areas of mainland China were evaluated using correlation coefficients (CC), absolute deviation (AD), relative deviation (RB), and five extreme precipitation indices; (2) The extreme precipitation estimates over 21 Chinese major cities were assessed with the two most important extreme indices, namely the 99th percentile of daily precipitation on wet days (R99) and total precipitation when daily precipitation exceeding R99 (R99TOT); and (3) Bivariate Moran's I (BMI) was adopted to assess the inner-city spatial correlation of R99 and R99TOT between SPPs and gauge observations in four major cities with most gauges. The results indicate that MSWEP has the highest CC of 0.79 and the lowest AD of 1.61 mm at the national scale. However, it tends to underestimate urban precipitation, with an RB of −8.5%. GSMaP_Gauge and IMERG performed better in estimating extreme values, with close extreme indices with gauge observations. According to the 21 major cities, GSMaP_Gauge also shows high accuracy in estimating R99 and R99TOT values, with the best RB and AD in these cities, while CMFD and MSWEP exhibit the highest CC values for R99 and R99TOT, respectively, indicating a strong correlation between their estimates and those obtained from gauge observations. At the inner-city scale, MSWEP shows advantages in monitoring the spatial distribution of urban extreme precipitation in most of cities. The study firstly provided the multiscale assessment of urban extreme precipitation by SPPs over mainland China, which is useful for their applications. [ABSTRACT FROM AUTHOR]