Ursolic acid(UA),a natural pentacyclic triterpenoid,possesses widespread biological and pharmacological activities.However,drawbacks such as low bioavailability,poor targeting and rapid metabolism greatly hinder its f...Ursolic acid(UA),a natural pentacyclic triterpenoid,possesses widespread biological and pharmacological activities.However,drawbacks such as low bioavailability,poor targeting and rapid metabolism greatly hinder its further clinical application.Recently,with the development of nanotechnology,various UA nanosystems have emerged as promising strategies for effective cancer therapy.This article reviews various types of UA-based nanodelivery systems,primarily with emphasis placed on novel UA-based carrier-free nanodrugs,which are considered to be innovative methods for cancer therapy.Moreover,this review presents carrier-free nano-drugs that co-assembled of UA and photosensitizers that displayed synergistic antitumor performance.Finally,the article also describes the development and challenges of UA nanosystems for future research in this field.Overall,the information presented in this review will provide new insight into the rational utilization of nano-drugs in cancer therapy.展开更多
Human activities modulate the impact of environmental forcing in general and of climate in particular.Information on the spatial and temporal patterns of human activities is in high demand,but scarce in sparsely popul...Human activities modulate the impact of environmental forcing in general and of climate in particular.Information on the spatial and temporal patterns of human activities is in high demand,but scarce in sparsely populated and data-poor regions such as Northern Africa.The intensity and spatial distribution of nighttime lights provide useful information on human activities and can be observed by space-borne imaging radiometers.Our study helps to bridge the gap between the DMSP-OLS data available until 2013 and the NPP-VIIRS data available since 2013.The approach to calibrate the OLS data includes three steps:a)inter-calibrate the OLS DN data acquired by different sensors in 1992-2013;b)cali-brate the OLS DN data using VIIRS data in 2013;c)generate syn-thetic OLS radiance data by degrading the VIIRS data in 2013-2020.We generated a)a time series of calibrated OLS nighttime light radiance data(1992-2013);b)mean annual VIIRS radiance on stable lights at the OLS spatial resolution for 2013-2020;c)synthetic OLS radiance data generated using VIIRS radiance data degraded to match the radiometric specifications of OLS for 2013-2020.The evaluation of these data products in 2013 documented their accu-racy and consistency.展开更多
基金supported by the National Natural Science Foundation of China(81972832,81472767)Scientific Research Training Program for Undergraduate of Fuzhou University(25055,25068)。
文摘Ursolic acid(UA),a natural pentacyclic triterpenoid,possesses widespread biological and pharmacological activities.However,drawbacks such as low bioavailability,poor targeting and rapid metabolism greatly hinder its further clinical application.Recently,with the development of nanotechnology,various UA nanosystems have emerged as promising strategies for effective cancer therapy.This article reviews various types of UA-based nanodelivery systems,primarily with emphasis placed on novel UA-based carrier-free nanodrugs,which are considered to be innovative methods for cancer therapy.Moreover,this review presents carrier-free nano-drugs that co-assembled of UA and photosensitizers that displayed synergistic antitumor performance.Finally,the article also describes the development and challenges of UA nanosystems for future research in this field.Overall,the information presented in this review will provide new insight into the rational utilization of nano-drugs in cancer therapy.
基金supported by the National Natural Science Foundation of China project(Grant No.41661144022)the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDA19030203),the Chinese Academy of Sciences President’s International Fellowship Initiative(Grant No.2020VTA0001),and the MOST High-Level Foreign Expert program(Grant No.GL20200161002).
文摘Human activities modulate the impact of environmental forcing in general and of climate in particular.Information on the spatial and temporal patterns of human activities is in high demand,but scarce in sparsely populated and data-poor regions such as Northern Africa.The intensity and spatial distribution of nighttime lights provide useful information on human activities and can be observed by space-borne imaging radiometers.Our study helps to bridge the gap between the DMSP-OLS data available until 2013 and the NPP-VIIRS data available since 2013.The approach to calibrate the OLS data includes three steps:a)inter-calibrate the OLS DN data acquired by different sensors in 1992-2013;b)cali-brate the OLS DN data using VIIRS data in 2013;c)generate syn-thetic OLS radiance data by degrading the VIIRS data in 2013-2020.We generated a)a time series of calibrated OLS nighttime light radiance data(1992-2013);b)mean annual VIIRS radiance on stable lights at the OLS spatial resolution for 2013-2020;c)synthetic OLS radiance data generated using VIIRS radiance data degraded to match the radiometric specifications of OLS for 2013-2020.The evaluation of these data products in 2013 documented their accu-racy and consistency.
