Bird predation during seed maturation causes great loss to agricultural production.In this study,through GWAS analysis of a large-scale sorghum germplasm diversity panel,we identified that Tannin1,which encodes a WD40...Bird predation during seed maturation causes great loss to agricultural production.In this study,through GWAS analysis of a large-scale sorghum germplasm diversity panel,we identified that Tannin1,which encodes a WD40 protein functioning in the WD40/MYB/bHLH complex,controls bird feeding behavior in sorghum.Metabolic profiling analysis showed that a group of sorghum accessions preferred by birds contain mutated tan1-a/b alleles and accumulate significantly lower levels of anthocyanins and condensed tannin compounds.In contrast,a variety of aromatic and fatty acid-derived volatiles accumulate at significantly higher levels in these bird-preference accessions.We subsequently conducted both sparrow feeding and sparrow volatile attractant assays,which confirmed,respectively,the antifeedant and attractant functions of these differentially accumulated metabolites.In addition,the connection between the biosynthesis pathway of anthocyanin and proanthocyanidin and the pathway of fatty acid–derived volatile biosynthesis was demonstrated by discovering that Tannin1 complex modulates fatty acid biosynthesis by regulating the expression of SbGL2 in sorghum,thus affecting the accumulation of fatty acid-derived volatiles.Taken together,our study identified Tannin1 as the gene underlying the major locus controlling bird feeding behavior in sorghum,illustrating an example of the identification of an ecologically impactful molecular mechanism from field observation and providing significant insights into the chemistry of bird–plant ecological interactions.展开更多
We analyzed and improved a collision avoidance strategy, which was supported by Long Term EvolutionVehicle(LTE-V)-based Vehicle-to-Vehicle(V2 V) communication, for automated vehicles. This work was completed in two st...We analyzed and improved a collision avoidance strategy, which was supported by Long Term EvolutionVehicle(LTE-V)-based Vehicle-to-Vehicle(V2 V) communication, for automated vehicles. This work was completed in two steps. In the first step, we analyzed the probability distribution of message transmission time, which was conditional on transmission distance and vehicle density. Our analysis revealed that transmission time exhibited a near-linear increase with distance and density. We also quantified the trade-off between high/low resource reselection probabilities to improve the setting of media access parameters. In the second step, we studied the required safety distance in accordance with the response time, i.e., the transmission time, derived on the basis of a novel concept of Responsibility-Sensitive Safety(RSS). We improved the strategy by considering the uncertainty of response time and its dependence on vehicle distance and density. We performed theoretical analysis and numerical testing to illustrate the effectiveness of the improved robust RSS strategy. Our results enhance the practicability of building driverless highways with special lanes reserved for the exclusive use of LTE-V vehicles.展开更多
Inhalation of reclaimed water is known to cause lung infammation,and free endotoxins have been shown to be a major risk factor for acute exposure.Subchronic exposure has also been shown to induce infammatory responses...Inhalation of reclaimed water is known to cause lung infammation,and free endotoxins have been shown to be a major risk factor for acute exposure.Subchronic exposure has also been shown to induce infammatory responses with visible tissue damage.However,subchronic risk factors have yet to be identified,and a threshold for the protection of occupational populations during urban reuse is necessary.In this study,potential risk factors in reclaimed water were examined by subchronic exposure with fractionated reclaimed water,and the health risk threshold was tested with a series of diluted reclaimed water.Accordingly,following a 12-week exposure,macromolecules and microorganisms were found to be two major risk factors in reclaimed water that could cause pulmonary infammation,including increased proportion of polymorphonuclear leukocytes in bronchoalveolar fuid,formation of inducible bronchus-associated lymphoid tissue,and elevation of Immunoglobulin A levels.Moreover,infammation persisted after a 4-week recovery period.The calculated threshold of reclaimed water exposure for mice was 31.8 Endotoxin Unit(EU)/(kg·day)under when exposed to 50%additional relative humidity from reclaimed water at 25℃ for 2 hr/day.Meanwhile,the subchronic threshold estimate for humans under the same exposure conditions was found to be 12.2 EU/(kg·day),corresponding to endotoxin levels of 61.7 EU/mL in reclaimed water.The threshold level of endotoxin was lower than that in most non-potable reclaimed water.The findings of this study suggest that occupational exposure of reclaimed water can serve as a potential risk to workers.展开更多
分布式可再生能源(Distributed Energy Resources,DER)以微电网的形式大规模并网,其稳定运行面临着挑战。针对微电网中可再生能源出力的不确定性及调控过程中柔性负荷调整量过大可能会使用户满意度下降的问题,建立了考虑DER出力不确定...分布式可再生能源(Distributed Energy Resources,DER)以微电网的形式大规模并网,其稳定运行面临着挑战。针对微电网中可再生能源出力的不确定性及调控过程中柔性负荷调整量过大可能会使用户满意度下降的问题,建立了考虑DER出力不确定性和计及用户满意度的日前优化调度模型。首先,采用基于条件风险价值(Conditional ValueatRisk,CVaR)理论对微电网不确定性风险进行量化处理,提高系统运行稳定性,并将其转化为风险成本。其次,将优化前后的新旧负荷曲线差异程度作为评判用户满意度大小的指标,在满足微电网经济运行的同时,提高用户侧的用电体验感。以微电网综合运行成本最小和用户满意度最大为目标函数,建立优化调度模型。最后,采用改进的NSGA-Ⅱ算法求解该模型,并通过仿真分析了不同置信水平及三种方案下的优化结果,从而验证了所提模型的有效性。展开更多
文摘Bird predation during seed maturation causes great loss to agricultural production.In this study,through GWAS analysis of a large-scale sorghum germplasm diversity panel,we identified that Tannin1,which encodes a WD40 protein functioning in the WD40/MYB/bHLH complex,controls bird feeding behavior in sorghum.Metabolic profiling analysis showed that a group of sorghum accessions preferred by birds contain mutated tan1-a/b alleles and accumulate significantly lower levels of anthocyanins and condensed tannin compounds.In contrast,a variety of aromatic and fatty acid-derived volatiles accumulate at significantly higher levels in these bird-preference accessions.We subsequently conducted both sparrow feeding and sparrow volatile attractant assays,which confirmed,respectively,the antifeedant and attractant functions of these differentially accumulated metabolites.In addition,the connection between the biosynthesis pathway of anthocyanin and proanthocyanidin and the pathway of fatty acid–derived volatile biosynthesis was demonstrated by discovering that Tannin1 complex modulates fatty acid biosynthesis by regulating the expression of SbGL2 in sorghum,thus affecting the accumulation of fatty acid-derived volatiles.Taken together,our study identified Tannin1 as the gene underlying the major locus controlling bird feeding behavior in sorghum,illustrating an example of the identification of an ecologically impactful molecular mechanism from field observation and providing significant insights into the chemistry of bird–plant ecological interactions.
基金supported in part by the National Natural Science Foundation of China (No. 61673233)Beijing Municipal Science and Technology Program (No. D171100004917001/2)the Key Technologies Research and Development Program of the Thirteenth Five-Year Plan of China (No. 2018YFB1600600)
文摘We analyzed and improved a collision avoidance strategy, which was supported by Long Term EvolutionVehicle(LTE-V)-based Vehicle-to-Vehicle(V2 V) communication, for automated vehicles. This work was completed in two steps. In the first step, we analyzed the probability distribution of message transmission time, which was conditional on transmission distance and vehicle density. Our analysis revealed that transmission time exhibited a near-linear increase with distance and density. We also quantified the trade-off between high/low resource reselection probabilities to improve the setting of media access parameters. In the second step, we studied the required safety distance in accordance with the response time, i.e., the transmission time, derived on the basis of a novel concept of Responsibility-Sensitive Safety(RSS). We improved the strategy by considering the uncertainty of response time and its dependence on vehicle distance and density. We performed theoretical analysis and numerical testing to illustrate the effectiveness of the improved robust RSS strategy. Our results enhance the practicability of building driverless highways with special lanes reserved for the exclusive use of LTE-V vehicles.
基金supported by the National Natural Science Foundation of China (Nos.51738005 and 21777084)。
文摘Inhalation of reclaimed water is known to cause lung infammation,and free endotoxins have been shown to be a major risk factor for acute exposure.Subchronic exposure has also been shown to induce infammatory responses with visible tissue damage.However,subchronic risk factors have yet to be identified,and a threshold for the protection of occupational populations during urban reuse is necessary.In this study,potential risk factors in reclaimed water were examined by subchronic exposure with fractionated reclaimed water,and the health risk threshold was tested with a series of diluted reclaimed water.Accordingly,following a 12-week exposure,macromolecules and microorganisms were found to be two major risk factors in reclaimed water that could cause pulmonary infammation,including increased proportion of polymorphonuclear leukocytes in bronchoalveolar fuid,formation of inducible bronchus-associated lymphoid tissue,and elevation of Immunoglobulin A levels.Moreover,infammation persisted after a 4-week recovery period.The calculated threshold of reclaimed water exposure for mice was 31.8 Endotoxin Unit(EU)/(kg·day)under when exposed to 50%additional relative humidity from reclaimed water at 25℃ for 2 hr/day.Meanwhile,the subchronic threshold estimate for humans under the same exposure conditions was found to be 12.2 EU/(kg·day),corresponding to endotoxin levels of 61.7 EU/mL in reclaimed water.The threshold level of endotoxin was lower than that in most non-potable reclaimed water.The findings of this study suggest that occupational exposure of reclaimed water can serve as a potential risk to workers.
文摘分布式可再生能源(Distributed Energy Resources,DER)以微电网的形式大规模并网,其稳定运行面临着挑战。针对微电网中可再生能源出力的不确定性及调控过程中柔性负荷调整量过大可能会使用户满意度下降的问题,建立了考虑DER出力不确定性和计及用户满意度的日前优化调度模型。首先,采用基于条件风险价值(Conditional ValueatRisk,CVaR)理论对微电网不确定性风险进行量化处理,提高系统运行稳定性,并将其转化为风险成本。其次,将优化前后的新旧负荷曲线差异程度作为评判用户满意度大小的指标,在满足微电网经济运行的同时,提高用户侧的用电体验感。以微电网综合运行成本最小和用户满意度最大为目标函数,建立优化调度模型。最后,采用改进的NSGA-Ⅱ算法求解该模型,并通过仿真分析了不同置信水平及三种方案下的优化结果,从而验证了所提模型的有效性。
