Marine natural products represent an important class of biologically active compounds critical for drug discovery.To date,17 marine-derived drugs,including trabectedin and eribulin,have been approved by the US FDA for...Marine natural products represent an important class of biologically active compounds critical for drug discovery.To date,17 marine-derived drugs,including trabectedin and eribulin,have been approved by the US FDA for clinical use and 33 others are in clinical trials[1].However,their medicinal investigation and clinical trials are often hampered by the scarcity of natural sources and by the difficulties of their harvesting in the delicate marine environment.Therefore,efficient and scalable approaches for the synthesis of promising marine natural products are essential to overcome supply issues for drug development.展开更多
High-spectral resolution infrared sounders on board satellites can measure atmospheric trace gases confined to the planetary boundary layer(PBL).However,their sensitivity to the PBL depends on the temperature differen...High-spectral resolution infrared sounders on board satellites can measure atmospheric trace gases confined to the planetary boundary layer(PBL).However,their sensitivity to the PBL depends on the temperature difference between the surface and the atmosphere,the so-called thermal contrast(TC).After reviewing the physical aspects of TC and how it drives measurement sensitivity,we characterize the global and temporal behavior of TC in clear-sky conditions.Combining land surface temperatures from the Copernicus Global Land Services dataset with air temperatures from the European Centre for Medium-Range Weather Forecasts reanalysis v5,we obtain global monthly averages of TC at high spatial(31 km)and temporal(1 h)resolution.TCs are analyzed as a function of time of the day,time of the year,location and land cover.Daytime maxima are observed from 1130 to 1330 local time,from 5-10 K in winter to 10-30 K in summer.A large dependency on land cover type is observed,both in the magnitude of the daily variations,and in the seasonality.For bare soils,shrublands,sparse and herbaceous vegetation,a maximum is seen in summer with daily TC amplitudes over 30 K.In contrast,for forests,wetlands,and croplands,the seasonal maximum occurs in spring,with daily variations below 15 K.Nighttime TCs typically range between−5 and−10 K.Occasionally,very favorable nighttime measurement conditions occur during winter and autumn due to large temperature inversions.Throughout the paper,we illustrate important concepts by means of satellite observations of NH3 over the Po Valley(Italy).展开更多
文摘Marine natural products represent an important class of biologically active compounds critical for drug discovery.To date,17 marine-derived drugs,including trabectedin and eribulin,have been approved by the US FDA for clinical use and 33 others are in clinical trials[1].However,their medicinal investigation and clinical trials are often hampered by the scarcity of natural sources and by the difficulties of their harvesting in the delicate marine environment.Therefore,efficient and scalable approaches for the synthesis of promising marine natural products are essential to overcome supply issues for drug development.
基金funding from the Belgian State Federal Office for Scientific,Technical and Cultural Affairs(Prodex HIRS)the Air Liquide Foundation(TAPIR project)+3 种基金supported by the FED-tWIN project ARENBERG(“Assessing the Reactive Nitrogen Budget and Emissions at Regional and Global Scales”)funded through the Belgian Science Policy Office(BELSPO)supported by the Belgian F.R.S.-FNRSsupport from a FRIA(Fund for scientific Research in Industry and Agriculture)grant from the Belgian F.R.S-FNRS.
文摘High-spectral resolution infrared sounders on board satellites can measure atmospheric trace gases confined to the planetary boundary layer(PBL).However,their sensitivity to the PBL depends on the temperature difference between the surface and the atmosphere,the so-called thermal contrast(TC).After reviewing the physical aspects of TC and how it drives measurement sensitivity,we characterize the global and temporal behavior of TC in clear-sky conditions.Combining land surface temperatures from the Copernicus Global Land Services dataset with air temperatures from the European Centre for Medium-Range Weather Forecasts reanalysis v5,we obtain global monthly averages of TC at high spatial(31 km)and temporal(1 h)resolution.TCs are analyzed as a function of time of the day,time of the year,location and land cover.Daytime maxima are observed from 1130 to 1330 local time,from 5-10 K in winter to 10-30 K in summer.A large dependency on land cover type is observed,both in the magnitude of the daily variations,and in the seasonality.For bare soils,shrublands,sparse and herbaceous vegetation,a maximum is seen in summer with daily TC amplitudes over 30 K.In contrast,for forests,wetlands,and croplands,the seasonal maximum occurs in spring,with daily variations below 15 K.Nighttime TCs typically range between−5 and−10 K.Occasionally,very favorable nighttime measurement conditions occur during winter and autumn due to large temperature inversions.Throughout the paper,we illustrate important concepts by means of satellite observations of NH3 over the Po Valley(Italy).
