Sand dust belts span approximately one-fifth of the global land surface.In these regions,dust tends to settle on vegetation surfaces,altering the observed reflectance and affecting remote sensing detections.To enhance...Sand dust belts span approximately one-fifth of the global land surface.In these regions,dust tends to settle on vegetation surfaces,altering the observed reflectance and affecting remote sensing detections.To enhance the accuracy of maize growth monitoring in dust-affected regions,this study aims to quantify the effect of sand dust retention on maize during the tasseling stage in the Kashgar Prefecture,Xinjiang Uygur Autonomous Region,China,by analyzing changes in canopy reflectance and vegetation indices.First,field sampling was conducted to measure the key canopy structure parameters and dust retention levels of maize,and laboratory spectral measurements were performed on leaf spectral properties under gradient dust retention.The measured data were then used to drive the LargE-Scale remote sensing data and image Simulation framework(LESS)model for simulating realistic maize canopy spectra across different dust levels,with validation against Sentinel-2 imagery.Second,on the basis of the simulated and satellite-derived spectra,the dust resistance of 36 common vegetation indices was systematically evaluated,and new robust dust-resistant indices were developed.The results showed that compared with dust-free maize,the canopy reflectance of dust-retained maize followed an increase–decrease–increase pattern,with critical turning points at 735 and 1325 nm.The maximum reflectance difference of–0.11755(change rate:29.002%)occurred within the 735–1325 nm range at 24 g/m^(2)dust retention,and the minimum reflectance difference of 0.04285(change rate:148.950%)was observed in the 350–735 nm range under the same dust retention level.Among the 36 vegetation indices,only the global environment monitoring index(GEMI)and the ratio of transformed chlorophyll absorption in reflectance index to optimized soil-adjusted vegetation index(TCARI/OSAVI)exhibited dust resistance,with GEMI being effective below 6 g/m^(2)and TCARI/OSAVI remaining stable across all levels(average ratio:0.970).The newly developed indices in this study,(RE3–RE2)/(NIR–RE2),(RE3–RE2)/(RE4–RE2),and(NIR–RE2)/(RE4–RE2),retained values within the predefined dust-resistant range over the full dust retention levels of 0–24 g/m^(2),thus showing a more stable dust resistance compared with the commonly used 36 vegetation indices.Specially,(RE3–RE2)/(RE4–RE2)performed the most robustly in Sentinel-2 imagery,that is,58.020%of pixels were within the dust-resistant range,and an average ratio of 0.937 was obtained for the original-spectra index.This study provides a scientific basis for crop monitoring and management in dust-affected regions.展开更多
Substantial defects are produced in Al2O3 by 4 MeV Au ion irradiation with a fluence of 4.4×10^15 cm^-2. Ruther- ford baekscattering spectrometry/channeling and cross-sectional transmission electron microscopy me...Substantial defects are produced in Al2O3 by 4 MeV Au ion irradiation with a fluence of 4.4×10^15 cm^-2. Ruther- ford baekscattering spectrometry/channeling and cross-sectional transmission electron microscopy methods are used to investigate the irradiation damage. The 190keV H ions with a fuence of 1×10^17 cm^-2 are used for implanting pristine and Au ion irradiated Al2O3 to explore the irradiation damage effects on the hydrogen retention in Al2O3. The time-of-flight secondary ion mass spectrometry method is used to obtaJn the single hydrogen depth profile and ions mass spectra （IMS）, in which we find that implanted hydrogens interacted with defects produced by Au ion irradiation. In IMS, we also obtain the hydrogen retention at a certain depth. Comparing the hydrogen retention in different Al2O3 samples, it is concluded that the irradiation damage improves the tritium permeation resistance property of Al2O3 under given conditions. This result means that Al2O3 may strengthen its property of reduc/ng tritium permeation under the harsh irradiation environment in fusion reactors.展开更多
Alternative splicing plays a vital role in plant immunity,but how plants stringently and selectively regulate alternative splicing to coordinate immunity and growth is poorly understood.Here,we report that H_(2)O_(2)-...Alternative splicing plays a vital role in plant immunity,but how plants stringently and selectively regulate alternative splicing to coordinate immunity and growth is poorly understood.Here,we report that H_(2)O_(2)-triggered phosphorylation of the RNA-binding protein RRM2R releases a retained-intron brake in OsMAPKKK18 encoding a mitogen-activated protein kinase kinase kinase to orchestrate plant immunity and growth in rice.We found that,without pathogen infection,OsMAPKKK18βtranscripts containing a retained intron are subjected to nonsense-mediated mRNA decay to promote plant growth.Upon Magnaporthe oryzae pathogen invasion,H_(2)O_(2)activates the protein kinase OsCLK1 to phosphorylate and stabilize RRM2R,which interacts with OsRNPS1A/B to recruit spliceosome machinery and promote the production of OsMAPKKK18αtranscripts without the retained intron to promote rice immunity.Furthermore,we revealed that after the endogenous H_(2)O_(2)is consumed or degraded by peroxidases or catalases,decreased abundance of RRM2R reduces the accumulation of OsMAPKKK18αtranscripts to avoid autoimmunity in rice.Taken together,the results of our study uncover H_(2)O_(2)-controlled OsMAPKKK18 intron retention as a novel molecular switch for orchestrating immunity and growth in rice.展开更多
Emergency retention basins (ERB) are diked enclosures alongside rivers into which water from the main river channel is diverted during extreme floods. If the basins are operated during extreme flooding, two negative e...Emergency retention basins (ERB) are diked enclosures alongside rivers into which water from the main river channel is diverted during extreme floods. If the basins are operated during extreme flooding, two negative environmental impacts may occur: 1) contamination of the soils due to their transport by suspended sediments to the basin and 2) depletion of dissolved oxygen in the basin water. A computer-based methodology is presented which was used to assess the environmental risk exhibited by the operation of an ERB system proposed for the Elbe River in Germany. The August 2002 extreme flood event was used as a test case. For such a flood, the results showed that there is a 77% risk that dissolved oxygen levels fall below 2 mg/L in the water and a 48% chance of exceeding the inspection value of 500 mg zinc/kg in the soil.展开更多
目的:分析黄连降糖汤联合二甲双胍治疗湿热内蕴证2型糖尿病(T2DM)的效果。方法:选取2021年4月—2023年1月武穴市中医医院内分泌科收治的75例湿热内蕴证T2DM患者,随机分为对照组(38例,二甲双胍治疗)和观察组(37例,黄连降糖汤联合二甲双...目的:分析黄连降糖汤联合二甲双胍治疗湿热内蕴证2型糖尿病(T2DM)的效果。方法:选取2021年4月—2023年1月武穴市中医医院内分泌科收治的75例湿热内蕴证T2DM患者,随机分为对照组(38例,二甲双胍治疗)和观察组(37例,黄连降糖汤联合二甲双胍治疗)。比较两组一般指标、中医证候评分、实验室指标。结果:治疗后,观察组腰围及臀围低于对照组(P<0.05);治疗后,观察组中医证候评分低于对照组(P<0.001);治疗后,观察组餐后2 h胰岛素、餐后2 h C肽、餐后2 h血糖水平低于对照组(P<0.05);治疗后,观察组总胆固醇、甘油三酯、低密度脂蛋白胆固醇水平低于对照组(P<0.05),高密度脂蛋白胆固醇水平高于对照组(P=0.017)。结论:黄连降糖汤联合二甲双胍可有效降低湿热内蕴证T2DM患者的腰围、臀围、血糖及血脂水平,改善胰岛素抵抗。展开更多
目的:在大鼠处于正畸牙保持期时,以全身施药辛伐他汀的方法,来研究其对牙周组织中骨形成蛋白2(bone morphogenetic protein 2,BMP-2)表达的影响。方法:选用78只8周龄雄性Wistar大鼠,随机分成3组。1)空白对照组:将大鼠的前牙实施连轧,将...目的:在大鼠处于正畸牙保持期时,以全身施药辛伐他汀的方法,来研究其对牙周组织中骨形成蛋白2(bone morphogenetic protein 2,BMP-2)表达的影响。方法:选用78只8周龄雄性Wistar大鼠,随机分成3组。1)空白对照组:将大鼠的前牙实施连轧,将其作为支抗,向近中的方向牵移上颌两侧的第一磨牙,持续进行21d之后将其处死。2)构建牙移动模型的对照组,21d之后,在左侧的上颌安装相应的保持装置,各保持1、3、7、14、21、28d,在保持期内,给予注射腹腔生理盐水。3)实验组:改组的保持及加力措施与对照组相同,在保持期期间,给予注射腹腔辛伐他汀。在保持期结束之后,采用免疫组化染色法,并结合定量分析法,对移动牙的牙周组织内的BMP-2水平进行检测和观察。结果:在整个保持期,对照组的BMP-2量逐渐减少,实验组呈逐渐增加的趋势。相同时间的实验用药组与实验对照组比较,实验组的BMP-2量较于对照组普遍要高。除了对照组中的第28天组之外,其余各小组BMP-2的表达强度均强于空白对照组(P<0.01)。结论:腹腔注射辛伐他汀能够增加大鼠实验性牙移动后保持阶段牙周组织中BMP-2的表达,从而促进骨细胞的生成、骨质矿化。展开更多
基金supported by the Fundamental Research Funds for the Central Universities(N2001020)the National Natural Science Foundation of China(41201359).
文摘Sand dust belts span approximately one-fifth of the global land surface.In these regions,dust tends to settle on vegetation surfaces,altering the observed reflectance and affecting remote sensing detections.To enhance the accuracy of maize growth monitoring in dust-affected regions,this study aims to quantify the effect of sand dust retention on maize during the tasseling stage in the Kashgar Prefecture,Xinjiang Uygur Autonomous Region,China,by analyzing changes in canopy reflectance and vegetation indices.First,field sampling was conducted to measure the key canopy structure parameters and dust retention levels of maize,and laboratory spectral measurements were performed on leaf spectral properties under gradient dust retention.The measured data were then used to drive the LargE-Scale remote sensing data and image Simulation framework(LESS)model for simulating realistic maize canopy spectra across different dust levels,with validation against Sentinel-2 imagery.Second,on the basis of the simulated and satellite-derived spectra,the dust resistance of 36 common vegetation indices was systematically evaluated,and new robust dust-resistant indices were developed.The results showed that compared with dust-free maize,the canopy reflectance of dust-retained maize followed an increase–decrease–increase pattern,with critical turning points at 735 and 1325 nm.The maximum reflectance difference of–0.11755(change rate:29.002%)occurred within the 735–1325 nm range at 24 g/m^(2)dust retention,and the minimum reflectance difference of 0.04285(change rate:148.950%)was observed in the 350–735 nm range under the same dust retention level.Among the 36 vegetation indices,only the global environment monitoring index(GEMI)and the ratio of transformed chlorophyll absorption in reflectance index to optimized soil-adjusted vegetation index(TCARI/OSAVI)exhibited dust resistance,with GEMI being effective below 6 g/m^(2)and TCARI/OSAVI remaining stable across all levels(average ratio:0.970).The newly developed indices in this study,(RE3–RE2)/(NIR–RE2),(RE3–RE2)/(RE4–RE2),and(NIR–RE2)/(RE4–RE2),retained values within the predefined dust-resistant range over the full dust retention levels of 0–24 g/m^(2),thus showing a more stable dust resistance compared with the commonly used 36 vegetation indices.Specially,(RE3–RE2)/(RE4–RE2)performed the most robustly in Sentinel-2 imagery,that is,58.020%of pixels were within the dust-resistant range,and an average ratio of 0.937 was obtained for the original-spectra index.This study provides a scientific basis for crop monitoring and management in dust-affected regions.
基金Supported by the National Natural Science Foundation of China under Grant Nos 91426304 and 91226202the National Magnetic Confinement Fusion Energy Research Project under Grant No 2015GB113000
文摘Substantial defects are produced in Al2O3 by 4 MeV Au ion irradiation with a fluence of 4.4×10^15 cm^-2. Ruther- ford baekscattering spectrometry/channeling and cross-sectional transmission electron microscopy methods are used to investigate the irradiation damage. The 190keV H ions with a fuence of 1×10^17 cm^-2 are used for implanting pristine and Au ion irradiated Al2O3 to explore the irradiation damage effects on the hydrogen retention in Al2O3. The time-of-flight secondary ion mass spectrometry method is used to obtaJn the single hydrogen depth profile and ions mass spectra （IMS）, in which we find that implanted hydrogens interacted with defects produced by Au ion irradiation. In IMS, we also obtain the hydrogen retention at a certain depth. Comparing the hydrogen retention in different Al2O3 samples, it is concluded that the irradiation damage improves the tritium permeation resistance property of Al2O3 under given conditions. This result means that Al2O3 may strengthen its property of reduc/ng tritium permeation under the harsh irradiation environment in fusion reactors.
基金funded by grants from the National Natural Science Foundation of China(32121003 and 32425005 to Xuewei Chen,32572382 to X.L.,32102227 to Q.X.,and 32272116 and 32072043 to J.W.)New Cornerstone Science Foundation(grant to Xuewei Chen),Central Guidance for Local Science and Technology Development Fund of Sichuan Province(2024ZYD0200 to X.L.)+1 种基金Biological Breeding-National Science and Technology Major Project(2023ZD04070 to J.W.)Natural Science Science Foundation of Sichuan Province(2024NSFTD0022 to J.W.,2024YFNH0014 to J.Yin,and 2023NSFSC1996 to W.Li).
文摘Alternative splicing plays a vital role in plant immunity,but how plants stringently and selectively regulate alternative splicing to coordinate immunity and growth is poorly understood.Here,we report that H_(2)O_(2)-triggered phosphorylation of the RNA-binding protein RRM2R releases a retained-intron brake in OsMAPKKK18 encoding a mitogen-activated protein kinase kinase kinase to orchestrate plant immunity and growth in rice.We found that,without pathogen infection,OsMAPKKK18βtranscripts containing a retained intron are subjected to nonsense-mediated mRNA decay to promote plant growth.Upon Magnaporthe oryzae pathogen invasion,H_(2)O_(2)activates the protein kinase OsCLK1 to phosphorylate and stabilize RRM2R,which interacts with OsRNPS1A/B to recruit spliceosome machinery and promote the production of OsMAPKKK18αtranscripts without the retained intron to promote rice immunity.Furthermore,we revealed that after the endogenous H_(2)O_(2)is consumed or degraded by peroxidases or catalases,decreased abundance of RRM2R reduces the accumulation of OsMAPKKK18αtranscripts to avoid autoimmunity in rice.Taken together,the results of our study uncover H_(2)O_(2)-controlled OsMAPKKK18 intron retention as a novel molecular switch for orchestrating immunity and growth in rice.
文摘Emergency retention basins (ERB) are diked enclosures alongside rivers into which water from the main river channel is diverted during extreme floods. If the basins are operated during extreme flooding, two negative environmental impacts may occur: 1) contamination of the soils due to their transport by suspended sediments to the basin and 2) depletion of dissolved oxygen in the basin water. A computer-based methodology is presented which was used to assess the environmental risk exhibited by the operation of an ERB system proposed for the Elbe River in Germany. The August 2002 extreme flood event was used as a test case. For such a flood, the results showed that there is a 77% risk that dissolved oxygen levels fall below 2 mg/L in the water and a 48% chance of exceeding the inspection value of 500 mg zinc/kg in the soil.
文摘目的:分析黄连降糖汤联合二甲双胍治疗湿热内蕴证2型糖尿病(T2DM)的效果。方法:选取2021年4月—2023年1月武穴市中医医院内分泌科收治的75例湿热内蕴证T2DM患者,随机分为对照组(38例,二甲双胍治疗)和观察组(37例,黄连降糖汤联合二甲双胍治疗)。比较两组一般指标、中医证候评分、实验室指标。结果:治疗后,观察组腰围及臀围低于对照组(P<0.05);治疗后,观察组中医证候评分低于对照组(P<0.001);治疗后,观察组餐后2 h胰岛素、餐后2 h C肽、餐后2 h血糖水平低于对照组(P<0.05);治疗后,观察组总胆固醇、甘油三酯、低密度脂蛋白胆固醇水平低于对照组(P<0.05),高密度脂蛋白胆固醇水平高于对照组(P=0.017)。结论:黄连降糖汤联合二甲双胍可有效降低湿热内蕴证T2DM患者的腰围、臀围、血糖及血脂水平,改善胰岛素抵抗。
文摘目的:在大鼠处于正畸牙保持期时,以全身施药辛伐他汀的方法,来研究其对牙周组织中骨形成蛋白2(bone morphogenetic protein 2,BMP-2)表达的影响。方法:选用78只8周龄雄性Wistar大鼠,随机分成3组。1)空白对照组:将大鼠的前牙实施连轧,将其作为支抗,向近中的方向牵移上颌两侧的第一磨牙,持续进行21d之后将其处死。2)构建牙移动模型的对照组,21d之后,在左侧的上颌安装相应的保持装置,各保持1、3、7、14、21、28d,在保持期内,给予注射腹腔生理盐水。3)实验组:改组的保持及加力措施与对照组相同,在保持期期间,给予注射腹腔辛伐他汀。在保持期结束之后,采用免疫组化染色法,并结合定量分析法,对移动牙的牙周组织内的BMP-2水平进行检测和观察。结果:在整个保持期,对照组的BMP-2量逐渐减少,实验组呈逐渐增加的趋势。相同时间的实验用药组与实验对照组比较,实验组的BMP-2量较于对照组普遍要高。除了对照组中的第28天组之外,其余各小组BMP-2的表达强度均强于空白对照组(P<0.01)。结论:腹腔注射辛伐他汀能够增加大鼠实验性牙移动后保持阶段牙周组织中BMP-2的表达,从而促进骨细胞的生成、骨质矿化。
