Marigolds(Tagetes spp.)are popular horticultural plants worldwide.The current study aimed to investigate the optimal mutagenic conditions for marigold seeds using EMS(ethyl methanesulfonate)mutagenesis.Different con-c...Marigolds(Tagetes spp.)are popular horticultural plants worldwide.The current study aimed to investigate the optimal mutagenic conditions for marigold seeds using EMS(ethyl methanesulfonate)mutagenesis.Different con-centrations and treatment times of EMS were applied to investigate their effects on the marigold seed germination rate,growth traits,antioxidant enzyme activities(i.e.,SOD and POD),and malondialdehyde(MDA)contents.Results indicated that with increasing the EMS treatment duration and concentration,the seed germination rate and growth treatments were reduced,accompanied by elevated MDA content.In addition,SOD and POD activ-ities initially correlated positively with the growth tratis at the lowest concentrations and shortest durations of EMS,but such relationship diminished beyond certain thresholds.The comprehensive analysis identified the opti-mal mutagenic conditions as 1%EMS treatment for 12 h,achieving a semi-lethal dose and enhancing stress-resis-tant components in seedlings.Thesefindings are pivotal for advancing genetic enhancement and germplasm innovation in marigolds.展开更多
Numerous studies have shown that intact tropical forests account for half of the total terrestrial sink for anthropogenic carbon dioxide.Here,we analyzed and compared changes in three main tropical forest regions from...Numerous studies have shown that intact tropical forests account for half of the total terrestrial sink for anthropogenic carbon dioxide.Here,we analyzed and compared changes in three main tropical forest regions from 2000 to 2014,based on time-series analysis and landscape metrics derived from moderate-resolution imaging spectroradiometer data.We examined spatialpattern changes in percentage of tree cover and net primary production(NPP)for three tropical forest regions—Amazon basin,Congo basin,and Southeast Asia.The results show that:the Amazon basin region had the largest tropical forest area and total NPP and a better continuity of TC distribution;the Southeast Asia region exhibited a sharp decrease in NPP and had comparatively separate spatial patterns of both TC and NPP;and the Congo basin region exhibited a dramatic increase in NPP and had better aggregation of forest NPP distribution.Results also show that aggregative patterns likely correlate with high NPP values.展开更多
Adjustments in foliar photoprotective pigments are crucial for plant adaptation to harsh environments,serving as indicators of environmental stress.However,understanding when and where these adjustments occur across d...Adjustments in foliar photoprotective pigments are crucial for plant adaptation to harsh environments,serving as indicators of environmental stress.However,understanding when and where these adjustments occur across diverse biomes remains unclear due to challenges in large-scale observation.Here,we propose a novel approach to assess dynamics in photoprotective pigments at the canopy level using a new index derived from spaceborne optical sensors.This approach generates a global map depicting the daily mean shortwave radiation threshold at which adjustments typically occur under prevailing climatic conditions.The global average of this threshold is 262±50 W m⁻2,with lower values at high latitudes and peaks near 40in both hemispheres.Temperature exerts a stronger influence on this latitudinal pattern than humidity.Future projections suggest a decrease in this threshold over northern high latitudes,implying exacerbated vulnerability under identical radiation levels due to negative warming responses.Based on this threshold,a high-stress zone around 60N is identified and is predicted to shift southward in the future.These findings bridge critical gaps in photoprotection research and offer a new perspective on understanding the biogeochemical cycles of global ecosystems.This framework can also enhance our ability to predict the fate of diverse ecosystems under future climate.展开更多
The Arctic is highly sensitive to climate change,and the rise in its near-surface air temperatures has been almost twice the global average.The increased growth of the Arctic tundra and its changing seasonality have b...The Arctic is highly sensitive to climate change,and the rise in its near-surface air temperatures has been almost twice the global average.The increased growth of the Arctic tundra and its changing seasonality have been observed,largely in response to the impacts of climate change.In this study,we investigated the temporal and spatial variations of the start of the growing season(SOS)using various remote sensing indices,including Normalized Difference Vegetation Index,Normalized Difference Water Index,and Normalized Difference Snow Index from 2000 to 2018 in Arctic tundra regions.The SOS was derived at 29 sites from ground observations,including CO2 flux data,phenological images,and field records that were used to validate the SOS from remote sensing indices.Our results revealed that the SOS was delayed by approximately 3.86 days per degree of latitude along the northward latitudinal gradient.From 2000 to 2018,the start of the growing season and the interannual variability differed greatly among tundra types.Although the overall trends were not significant from 2000 to 2018,the start of the growing season in different plant communities was consistently delayed after 2016.High Arctic vegetation,including(1)low wetland complexes(5–10 cm)dominated by sedges,grasses,and mosses,and(2)slightly higher prostrate and hemi-prostrate shrubs(<15 cm),experienced a delayed start of the growing season.The start of the growing season of Low Arctic vegetation,comprising(1)wetland complexes(10–40 cm)dominated by sedges,grasses,mosses,and dwarf shrubs,(2)moist tundra(20–50 cm)dominated by tussock cottongrass and dwarf shrubs,and(3)transition zones containing tundra and taiga,displayed no obvious trend.展开更多
The ACE inhibitory peptides have been characterized from the enzymatic digestion product of bighead carp protein and bioconjugated with graphene oxide(GO)to enhance its activity.The results showed that aspartic acid a...The ACE inhibitory peptides have been characterized from the enzymatic digestion product of bighead carp protein and bioconjugated with graphene oxide(GO)to enhance its activity.The results showed that aspartic acid and glutamic acid had the highest levels in ultrafiltration fractions(<5 kDa),where eight potential ACE inhibitory peptides were also identified(ADSNHKAF,KLWHHTF,LLRLHF,PPSEPTKL,VEKFPLF,YLRLHF,YYKLKPLL,YYKLKPML).Among the eight peptides,YLRLHF showed the best ACE inhibitory activity(IC50=121.90μM)and was a competitive inhibitor.Molecular docking experiments showed that YLRLHF formed four hydrogen bond interactions in the ACE protein pocket,coordination bonding with Zn^(2+),and π-πconjugation interactions to His421.GO elevated the ACE inhibitory activity of YLRLHF(at 0.1 mg/mL)from 43.36%to 51.72%.The structural characterization results obtained from FI-IR,XPS,SEM,and TEM demonstrated the successful combination of GO and YLRLHF.Additionally,biocouples of ACE inhibitory peptides from bighead carp proteins with GO might be potential candidates for future functional foods and antihypertensive drugs.展开更多
As an important advanced technique in the field of Earth observations,Synthetic Aperture Radar(SAR)plays a key role in the study of global environmental change,resources exploration,disaster mitigation,urban environme...As an important advanced technique in the field of Earth observations,Synthetic Aperture Radar(SAR)plays a key role in the study of global environmental change,resources exploration,disaster mitigation,urban environments,and even lunar exploration.However,studies on imaging,image processing,and Earth factor inversions have often been conducted independently for a long time,which significantly limits the application effectiveness of SAR remote sensing due to the lack of an overall integrated design scheme and integrated information processing.Focusing on this SAR application issue,this paper proposes and describes a new SAR data processing methodology–SAR data integrated processing(DIP)oriented on Earth environment factor inversions.The simple definition,typical integrated modes and overall implementation ideas are introduced.Finally,focusing on building information extraction(man-made targets)and sea ice classification(natural targets)applications,three SAR DIP methods and experiments are conducted.Improved results are obtained under the guidance of the SAR DIP framework.Therefore,the SAR DIP theoretical framework and methodology represent a new SAR science application mode that has the capability to improve the SAR remote sensing quantitative application level and promote the development of new theories and methodologies.展开更多
基金This work was supported by Yunnan Provincial Department of Science and Technology Key R&D Plan(202303AM140018,202303AK140029,202303AK140028)Yunnan Flower Breeding Key Experiment Open Foundation(FKL-202203)+2 种基金Yunnan Provincial Department of Science and Technology Science and Technology Project Agriculture Joint Foundation(202301BD070001-208)Yunnan Provincial Expert Basic Research Workstation FoundationWe also acknowledge the financial support from the Researchers Supporting Project(RSPD2025R751),King Saud University,Riyadh,Saudi Arabia.
文摘Marigolds(Tagetes spp.)are popular horticultural plants worldwide.The current study aimed to investigate the optimal mutagenic conditions for marigold seeds using EMS(ethyl methanesulfonate)mutagenesis.Different con-centrations and treatment times of EMS were applied to investigate their effects on the marigold seed germination rate,growth traits,antioxidant enzyme activities(i.e.,SOD and POD),and malondialdehyde(MDA)contents.Results indicated that with increasing the EMS treatment duration and concentration,the seed germination rate and growth treatments were reduced,accompanied by elevated MDA content.In addition,SOD and POD activ-ities initially correlated positively with the growth tratis at the lowest concentrations and shortest durations of EMS,but such relationship diminished beyond certain thresholds.The comprehensive analysis identified the opti-mal mutagenic conditions as 1%EMS treatment for 12 h,achieving a semi-lethal dose and enhancing stress-resis-tant components in seedlings.Thesefindings are pivotal for advancing genetic enhancement and germplasm innovation in marigolds.
基金supported by the National Key Research and Development Program of China(Grant No.2016YFA0600304)the International Partnership Program of Chinese Academy of Sciences(Grant No.131C11KYSB20160061)the Hainan Provincial Department of Science and Technology(Grant No.ZDKJ2016021)
文摘Numerous studies have shown that intact tropical forests account for half of the total terrestrial sink for anthropogenic carbon dioxide.Here,we analyzed and compared changes in three main tropical forest regions from 2000 to 2014,based on time-series analysis and landscape metrics derived from moderate-resolution imaging spectroradiometer data.We examined spatialpattern changes in percentage of tree cover and net primary production(NPP)for three tropical forest regions—Amazon basin,Congo basin,and Southeast Asia.The results show that:the Amazon basin region had the largest tropical forest area and total NPP and a better continuity of TC distribution;the Southeast Asia region exhibited a sharp decrease in NPP and had comparatively separate spatial patterns of both TC and NPP;and the Congo basin region exhibited a dramatic increase in NPP and had better aggregation of forest NPP distribution.Results also show that aggregative patterns likely correlate with high NPP values.
基金cofunded by the Innovative Research Program of the International Research Center of Big Data for Sustainable Development Goals(CBAS2022IRP03)the National Science Foundation of China(42276241)the International Joint Research Project of Chinese Academy of Sciences(183611KYSB20200059).
文摘Adjustments in foliar photoprotective pigments are crucial for plant adaptation to harsh environments,serving as indicators of environmental stress.However,understanding when and where these adjustments occur across diverse biomes remains unclear due to challenges in large-scale observation.Here,we propose a novel approach to assess dynamics in photoprotective pigments at the canopy level using a new index derived from spaceborne optical sensors.This approach generates a global map depicting the daily mean shortwave radiation threshold at which adjustments typically occur under prevailing climatic conditions.The global average of this threshold is 262±50 W m⁻2,with lower values at high latitudes and peaks near 40in both hemispheres.Temperature exerts a stronger influence on this latitudinal pattern than humidity.Future projections suggest a decrease in this threshold over northern high latitudes,implying exacerbated vulnerability under identical radiation levels due to negative warming responses.Based on this threshold,a high-stress zone around 60N is identified and is predicted to shift southward in the future.These findings bridge critical gaps in photoprotection research and offer a new perspective on understanding the biogeochemical cycles of global ecosystems.This framework can also enhance our ability to predict the fate of diverse ecosystems under future climate.
基金supported by the National Natural Science Foundation of China(Grant No.41875107)the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDA19070203)。
文摘The Arctic is highly sensitive to climate change,and the rise in its near-surface air temperatures has been almost twice the global average.The increased growth of the Arctic tundra and its changing seasonality have been observed,largely in response to the impacts of climate change.In this study,we investigated the temporal and spatial variations of the start of the growing season(SOS)using various remote sensing indices,including Normalized Difference Vegetation Index,Normalized Difference Water Index,and Normalized Difference Snow Index from 2000 to 2018 in Arctic tundra regions.The SOS was derived at 29 sites from ground observations,including CO2 flux data,phenological images,and field records that were used to validate the SOS from remote sensing indices.Our results revealed that the SOS was delayed by approximately 3.86 days per degree of latitude along the northward latitudinal gradient.From 2000 to 2018,the start of the growing season and the interannual variability differed greatly among tundra types.Although the overall trends were not significant from 2000 to 2018,the start of the growing season in different plant communities was consistently delayed after 2016.High Arctic vegetation,including(1)low wetland complexes(5–10 cm)dominated by sedges,grasses,and mosses,and(2)slightly higher prostrate and hemi-prostrate shrubs(<15 cm),experienced a delayed start of the growing season.The start of the growing season of Low Arctic vegetation,comprising(1)wetland complexes(10–40 cm)dominated by sedges,grasses,mosses,and dwarf shrubs,(2)moist tundra(20–50 cm)dominated by tussock cottongrass and dwarf shrubs,and(3)transition zones containing tundra and taiga,displayed no obvious trend.
基金The research was funded by the National Key R&D Program of China(2019YFD0901805).
文摘The ACE inhibitory peptides have been characterized from the enzymatic digestion product of bighead carp protein and bioconjugated with graphene oxide(GO)to enhance its activity.The results showed that aspartic acid and glutamic acid had the highest levels in ultrafiltration fractions(<5 kDa),where eight potential ACE inhibitory peptides were also identified(ADSNHKAF,KLWHHTF,LLRLHF,PPSEPTKL,VEKFPLF,YLRLHF,YYKLKPLL,YYKLKPML).Among the eight peptides,YLRLHF showed the best ACE inhibitory activity(IC50=121.90μM)and was a competitive inhibitor.Molecular docking experiments showed that YLRLHF formed four hydrogen bond interactions in the ACE protein pocket,coordination bonding with Zn^(2+),and π-πconjugation interactions to His421.GO elevated the ACE inhibitory activity of YLRLHF(at 0.1 mg/mL)from 43.36%to 51.72%.The structural characterization results obtained from FI-IR,XPS,SEM,and TEM demonstrated the successful combination of GO and YLRLHF.Additionally,biocouples of ACE inhibitory peptides from bighead carp proteins with GO might be potential candidates for future functional foods and antihypertensive drugs.
基金This study was supported by the Key project of National Natural Science Foundation of China(No.61132006)the Major project of National Natural Science Foundation of China(No.41590852).
文摘As an important advanced technique in the field of Earth observations,Synthetic Aperture Radar(SAR)plays a key role in the study of global environmental change,resources exploration,disaster mitigation,urban environments,and even lunar exploration.However,studies on imaging,image processing,and Earth factor inversions have often been conducted independently for a long time,which significantly limits the application effectiveness of SAR remote sensing due to the lack of an overall integrated design scheme and integrated information processing.Focusing on this SAR application issue,this paper proposes and describes a new SAR data processing methodology–SAR data integrated processing(DIP)oriented on Earth environment factor inversions.The simple definition,typical integrated modes and overall implementation ideas are introduced.Finally,focusing on building information extraction(man-made targets)and sea ice classification(natural targets)applications,three SAR DIP methods and experiments are conducted.Improved results are obtained under the guidance of the SAR DIP framework.Therefore,the SAR DIP theoretical framework and methodology represent a new SAR science application mode that has the capability to improve the SAR remote sensing quantitative application level and promote the development of new theories and methodologies.
