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Near-infrared (NIR, 700-1700 nm) bioimaging has gained considerable attention in recent years owing to its high imaging resolution and increasing penetration depth of tissues. NIR emissive ... lanthanide( iii ) complexes have emerged as alluring candidates for the design of NIR molecular probes in clinical imaging and diagnosis because of their desirable temporal-spatial resolution, negligible photobleaching effect, long lifetime and low biotoxicity. In this mini-review, we summarize our efforts in the molecular design of NIR luminescent lanthanide porphyrinoids and their biological applications in bioimaging and further clinical diagnosis and treatment. Remarkably, β-fluorinated porphyrin Yb 3+ probes exhibit high luminescence (5-13% quantum yields in H 2 O), long decay lifetimes (>100 μs) and enable in vivo fluorescence intensity imaging and time-resolved fluorescence lifetime imaging (FLIM). Finally, the main concerns and challenges for NIR emissive Ln biolabels such as the diversity of the NIR Ln 3+ optical toolbox and their biocompatibility and targeting capability in biological media are discussed so as to facilitate the long-term development of lanthanide chemical biology. The recent developments and prospects of near-infrared molecular probes based on luminescent lanthanide coordination complexes in bioimaging are described, which is important to emphasise the importance of lanthanide chemical biology. more

Evapotranspiration (ET) is an essential parameter in the water cycle and surface energy balance. Accurate estimation of daytime or daily ET is of great significance for many activities in human ... economic and social development. This study aims to propose a novel method for estimating daytime average ET by using temporal measurements of land surface temperature (LST) and net surface shortwave radiation (NSSR), following a previous developed elliptical relationship between diurnal cycles of LST and NSSR under cloud-free days. The method was primarily developed from the simulated data of a physics-based Atmosphere-Land Exchange (ALEX) model under different underlying surfaces and atmospheric conditions. Based on the simulated data, the proposed method showed considerable accuracy with the overall coefficient of determination ( R 2 ) of 0.958 and the root mean square error (RMSE) of 25.3 Wm -2 . In addition, ground ET measurements at four Ameriflux sites (US-ARM, US-SRM, US-Whs, and US-Wkg) during the 2018 growing season were collected to assess the estimated daytime average ET. Results show an overall RMSE of 64.7 Wm -2 for the estimated ET at the four sites, and the US-Whs site reveals a best accuracy ( R 2 =0.825, RMSE=44.4 Wm -2 ). These results indicated a potential for generating daytime ET with geostationary satellite observations at regional scales in future development. more

Bushen-Tiaojing-Fang (BSTJF) is commonly used to treat infertility. This study investigated the effects of BSTJF on the pregnancy outcomes of patients with repeated controlled ovarian stimulation ... (COS), on mitochondrial function, and on oxidative stress in ovarian granulosa cells (GCs) and follicular fluid (FF). The samples and clinical data of 97 patients, including 35 in the control group, 29 in the placebo group and 33 in the BSTJF group, were collected for this study. The mitochondrial ultrastructure, ATP content, mitochondrial DNA (mtDNA) number, 8-hydroxy-2-deoxyguanosine (8-OHdG), Mn-superoxide dismutase (Mn-SOD), glutathione peroxidase (GSH-Px) activity levels, and mRNA expression levels of Mn-SOD, GSH-Px, and nuclear factor erythroid-derived factor 2-related factor 2 (Nrf2) were analyzed. The high-grade embryo (P < 0.001), implantation (P = 0.033), and clinical pregnancy (P = 0.031) rates, as well as the ATP content (P = 0.014), mtDNA number (P = 0.035), GSH-Px activity (P = 0.004 in GCs and P = 0.008 in FF) and mRNA expression levels (P = 0.019), were significantly lower in the placebo group than in the control group, whereas the 8-OHdG content was significantly (P = 0.006 in FF) higher in the placebo group than in the control group. Compared with those in the placebo group, the high-grade embryo rate (P = 0.007), antioxidant enzyme activity (P = 0.037 and 0.036 in Mn-SOD; P = 0.047 and 0.030 in GSH-Px) and mRNA level (P < 0.001 in Nrf2, P = 0.039 in Mn-SOD and P = 0.002 in GSH-Px) were significantly higher in the BSTJF group, as were changes in mitochondrial ultrastructure, ATP (P = 0.040) and mtDNA number (P = 0.013). In conclusion, BSTJF can improve oxidative stress in patients with repeated COS and pregnancy outcomes. more

A ship motion time series (SMTS) exhibits obvious periodicity under the effects of periodic wave and strong nonlinearity owing to wind, ocean currents, and the load of ship itself, which make ... accurate forecasting difficult. To improve forecasting accuracy, this investigation divides the SMTS into a periodic term and a nonlinear term and forecasts each term separately. First, the periodogram estimation method (PEM) is implemented to forecast the periodic term. Then, owing to the strong nonlinearity of SMTS, the LSSVR model is used to forecast the nonlinear residual term that is generated by the PEM. On account of parameters that determine the predictive accuracy of the LSSVR model, the chaotic cloud particle swarm optimization (CCPSO) algorithm is introduced to optimize the parameters of the LSSVR model. Finally, combining the PEM, LSSVR model, and CCPSO algorithm, a hybrid forecasting method for SMTS, PEM&LSSVR-CCPSO, is developed. Subsequently, SMTS data for two ships that are sailing on the ocean are used as a numerical example, and thus, the forecasting performance of the presented method is evaluated. The results of the analysis demonstrate that the proposed hybrid SMTS forecasting scheme has better forecasting performance than classical forecasting models that are considered herein. more

Pancreatic ductal adenocarcinoma (PDAC) is a lethal malignancy with high mortality. Lack of effective treatment makes novel therapeutic discovery an urgent demand in PDAC research. By screening an ... epigenetic-related compound library, we identified THZ1, a covalent inhibitor of CDK7, as a promising candidate. Multiple long-established and patient-derived PDAC cell lines (PDC) were used to validate the efficacy of THZ1 in vitro. In addition, patient-derived xenograft (PDX) models and animal models of PDAC were utilized for examining THZ1 efficacy in vivo. Furthermore, RNA-Seq analyse was performed to reveal the molecular mechanism of THZ1 treatment. Finally, PDAC cell lines with primary or acquired resistance to THZ1 were investigated to explore the potential mechanism of THZ1 susceptibility. CDK7 inhibition was identified as a selective and potent therapeutic strategy for PDAC progression in multiple preclinical models. Mechanistic analyses revealed that CDK7 inhibition led to a pronounced downregulation of gene transcription, with a preferential repression of mitotic cell cycle and NF-κB signaling-related transcripts. MYC transcriptional was found to be involved in susceptibility of PDAC cells to CDK7 inhibition. In conclusion, Identification of CDK7-dependent transcriptional addiction in PDACs provides a potent therapeutic strategy that targets highly aggressive pancreatic cancer. more

In recent years, concern around the impact of pharmaceuticals and personal care products (PPCPs) on the environment has grown. In order to investigate the influence of tourists on emissions and ... ecological risk of PPCPs, the concentrations of thirty PPCPs were measured in influent and effluent from the four largest wastewater treatment plants, as well as surface river water at six sites in a famous tourist city (Sanya City, China). Substantial increasing trends on PPCPs levels were observed from low to high tourist season (ng/L to µg/L, or µg/L to mg/L). Caffeine (CAF) was dominant with concentrations as high as 185 µg/L. Emission load per capita was estimated to explore the contribution of different populations. Tourist migrant population might be a dominant contributor, as they were mostly elderly people who took long-term medication. The predicted no-effect concentration was derived using the species sensitivity distribution method to calculate the ecological risk quotient (RQ) of the dominant PPCPs. Additionally, RQs of seven dominant PPCPs in rivers were > 1, indicating high chronic ecological risk for freshwater ecosystems. The results of this study will assist in raising the awareness and improving management of emerging pollutants in less industrialized regions. more

Previous research on older adults who are widowed often focuses on the immediate subjective impacts of spousal loss, and how gender might influence this. Our interest here is on the factors that ... influence subjective well-being after a period of at least two years’ post-bereavement, and how this might differ for men and women. We draw on theoretical considerations from previous research on gender and on widowhood and use two different measures—life satisfaction and happiness—to assess possible differences in this subjective outcome. We used data from the 2014 Health and Retirement Study on 692 widowed adults aged 65 and over (578 females and 114 males) and employed regression and postestimation analyses to examine whether and how gender influences their subjective well-being. Our findings show that gender did not affect overall levels of subjective well-being, regardless of measure. However, gender did influence the predictors, such as total household income, total wealth, and social support from children and friends, for life satisfaction and happiness somewhat differently. Our study highlights the importance of examining gender differences among older widows and widowers and also underlines the importance of introducing different measures of subjective well-being that might yield different yet valuable findings. more

乡村生态文明建设是海南生态省建设的重要内容.通过培育“文明生态村”、打造“美丽乡村”,海南省乡村生态文明建设进入提质增效的生态产业化阶段,为乡村迎来了发展机遇.生态系统生产总值核算可以通过在乡村尺度上计算生态系统产品与服务的价值,起到监督、评价生态文明建设进展,探寻生态保护与乡村经济发展的平衡点,为实现彼此增益提供科学的数据支撑.同时,生态系统生产总值核算可以客观呈现当前乡村的生态价值,以此可以吸引资本、技术、人才等要素向农村流动,推动绿水青山变成金山银山.研究以海南省三亚市天涯区文门村为例,基于生态系统生产总值核算理论,对其生态系统产品与服务功能量和价值量进行核算.结果 表明,文门村2017年生态系统生产总值是10297.79万元,生态系统产品价值占24.93％,调节服务价值占75.07％,单位面积生态系统生态总值为5.06万元/hm2.调节服务价值中,水源涵养、洪水调蓄、固碳释氧和空气净化价值分别为3287.44万元、1593.32万元、2815.31万元和34.72万元;林地对生态调节服务价值的贡献最大,达到5378.33万元,约占总间接价值的69.57％,其次为耕地和园地生态系统,约占总间接价值的14.86％和11.66％.今后随着乡村生态文明建设的深入,自然资源管理制度的健全,生态农业与乡村旅游有机融合等建设内容的推进,乡村生态系统生产总值核算的内容需要进一步扩充.