Offshore wind farms are becoming increasingly distant from onshore centralized control centers,and the communication delays between them inevitably introduce time delays in the measurement signal of the primary freque...Offshore wind farms are becoming increasingly distant from onshore centralized control centers,and the communication delays between them inevitably introduce time delays in the measurement signal of the primary frequency control.This causes a deterioration in the performance of the primary frequency control and,in some cases,may even result in frequency instability within the power system.Therefore,a frequency response model that incorporates communication delays was established for power systems that integrate offshore wind power.The Padéapproximation was used to model the time delays,and a linearized frequency response model of the power system was derived to investigate the frequency stability under different time delays.The influences of the wind power proportion and frequency control parameters on the system frequency stability were explored.In addition,a Smith delay compensation control strategy was devised to mitigate the effects of communication delays on the system frequency dynamics.Finally,a power system incorporating offshore wind power was constructed using the MATLAB/Simulink platform.The simulation results demonstrate the effectiveness and robustness of the proposed delay compensation control strategy.展开更多
The power grid,as the hub connecting the power supply and consumption sides,plays an important role in achieving carbon neutrality in China.In emerging carbon markets,assessing the investment benefits of power-grid en...The power grid,as the hub connecting the power supply and consumption sides,plays an important role in achieving carbon neutrality in China.In emerging carbon markets,assessing the investment benefits of power-grid enterprises is essential.Thus,studying the impact of the carbon market on the investment and operation of powergrid enterprises is key to ensuring their efficient operation.Notably,few studies have examined the interaction between the carbon and electricity markets using system dynamics models,highlighting a research gap in this area.This study investigates the impact of the carbon market on the investment of power-grid enterprises using a novel evaluation system based on a system dynamics model that considers carbon-emissions from an established carbon-emission accounting model.First,an index system for benefit evaluation was constructed from six aspects:financing ability,economic benefit,reliability,social responsibility,user satisfaction,and carbon-emissions.A system dynamics model was then developed to reflect the causal feedback relationship between the impact of the carbon market on the investment and operation of power-grid enterprises.The simulation results of a provincial power-grid enterprise analyze comprehensive investment evaluation benefits over a 10-year period and the impact of carbon emissions on the investment and operation of power-grid enterprises.This study provides guidelines for the benign development of power-grid enterprises within the context of the carbon market.展开更多
Actinidia arguta is a berry fruit with high nutritional values.To evaluate the comprehensive quality,the fruit weight,titratable acid(TAC),soluble solids(SSC),vitamin C,mineral elements,and taste value of67 accessions...Actinidia arguta is a berry fruit with high nutritional values.To evaluate the comprehensive quality,the fruit weight,titratable acid(TAC),soluble solids(SSC),vitamin C,mineral elements,and taste value of67 accessions of A.arguta were measured,and sensory attributes including olfactive intensity,juiciness,sweetness,sourness,and astringency were assessed.Cluster analysis was carried out based on mineral elements,and principal component analysis(PCA)was used for comprehensive score ranking.The result demonstrated that fruit weight ranged from 3.5 g to 24.2 g,SSC ranged from 11.94%to 20.56%,TAC ranged from 0.15%to 1.20%,and vitamin C ranged from 3.51 g/kg to 230.76 g/kg(fresh weight)among the tested samples.There were significant differences in sourness,sweetness,bitterness,and umami among the 67 accessions based on electronic tongue analysis,and this result was rapidly and objectively characterized by the sensory assessment.The dendrogram was obtained and clustered the accessions into two major clusters,and five principal components were extracted by PCA.Overall,the information provided by this study identified the 10 best germplasm resources for fresh-eating and processing fruits.It can provide theoretical reference for nutritional efficacy evaluation and food development of A.arguta.展开更多
Dear Editor,The RAS gene is one of the most frequent oncogenes in human cancers,with significantly different mutation frequencies.The RAS family contains three isoforms:KRAS,HRAS and NRAS,with the KRAS mutations being...Dear Editor,The RAS gene is one of the most frequent oncogenes in human cancers,with significantly different mutation frequencies.The RAS family contains three isoforms:KRAS,HRAS and NRAS,with the KRAS mutations being more common than the other two.The KRAS mutation rate varies in non-small cell lung cancer(NSCLC)patients of different races:27%in Caucasians[1]and approximately 10%in Asians[2,3].Recently,the U.S.Food and Drug Administration(FDA)approved sotorasib(AMG510)and adagrasib(MRTX849)for the treatment of metastatic NSCLC harboring KRAS G12C mutations.In the face of novel treatment choices for KRAS-mutated NSCLC,it is indispensable to learn more about the systemic treatment of these patients.Clinical studies have shown that Caucasian patients with KRAS-mutated NSCLC had poor outcomes following first-line chemotherapy[4,5].However,studies on treatment outcomes of Asian patients with KRAS-mutated NSCLC are lacking.As the overwhelming majority of cases are diagnosed with lung adenocarcinoma,the standard first-line treatment for metastatic disease is pemetrexed-based doublet chemotherapy in combination with bevacizumab and/or immunotherapy in China.Herein,we investigated the clinical characteristics of KRAS mutation subtypes,co-occurring genomic alterations,and efficacy of first-line pemetrexed-platinum chemotherapy in Chinese KRAS-mutated NSCLC patients.展开更多
Complexing self-assembled DNA nanostructures with various functional guest species is the key to unlocking new and exciting biomedical applications.Cationic guest species not only induce magnesium-free DNA to self-ass...Complexing self-assembled DNA nanostructures with various functional guest species is the key to unlocking new and exciting biomedical applications.Cationic guest species not only induce magnesium-free DNA to self-assemble into defined structures but also endow the final complex nanomaterials with new properties.Herein,we propose a novel strategy that employs naturally occurring cationic amino acids to induce DNA self-assembly into defined nanostructures.Natural L-arginine and L-lysine can readily induce the assembly of tile-based DNA nanotubes and DNA origami sheets in a magnesium-free manner.The self-assembly processes are demonstrated to be pH-and concentration-dependent and are achieved at constant temperatures.Moreover,the assembled DNA/amino acid complex nanomaterials are stable at a physiological temperature of 37◦C.Substituting L-arginine with its D form enhances its serum stability.Further preliminary examination of this complex nanomaterial platform for biomedical applications indicates that DNA/amino acids exhibit distinct cellular uptake behaviors compared with their magnesium-assembled counterparts.The nanomaterial mainly clusters around the cell membrane and might be utilized to manipulate molecular events on the membrane.Our study suggests that the properties of DNA nanostructures can be tuned by complexing them with customized guest molecules for a designed application.The strategy proposed herein might be promising to advance the biomedical applications of DNA nanostructures.展开更多
基金the support of the National Natural Science Foundation of China(52077061)Fundamental Research Funds for the Central Universities(B240201121).
文摘Offshore wind farms are becoming increasingly distant from onshore centralized control centers,and the communication delays between them inevitably introduce time delays in the measurement signal of the primary frequency control.This causes a deterioration in the performance of the primary frequency control and,in some cases,may even result in frequency instability within the power system.Therefore,a frequency response model that incorporates communication delays was established for power systems that integrate offshore wind power.The Padéapproximation was used to model the time delays,and a linearized frequency response model of the power system was derived to investigate the frequency stability under different time delays.The influences of the wind power proportion and frequency control parameters on the system frequency stability were explored.In addition,a Smith delay compensation control strategy was devised to mitigate the effects of communication delays on the system frequency dynamics.Finally,a power system incorporating offshore wind power was constructed using the MATLAB/Simulink platform.The simulation results demonstrate the effectiveness and robustness of the proposed delay compensation control strategy.
基金supported by the National Natural Science Foundation of China(Grant No.52107087).
文摘The power grid,as the hub connecting the power supply and consumption sides,plays an important role in achieving carbon neutrality in China.In emerging carbon markets,assessing the investment benefits of power-grid enterprises is essential.Thus,studying the impact of the carbon market on the investment and operation of powergrid enterprises is key to ensuring their efficient operation.Notably,few studies have examined the interaction between the carbon and electricity markets using system dynamics models,highlighting a research gap in this area.This study investigates the impact of the carbon market on the investment of power-grid enterprises using a novel evaluation system based on a system dynamics model that considers carbon-emissions from an established carbon-emission accounting model.First,an index system for benefit evaluation was constructed from six aspects:financing ability,economic benefit,reliability,social responsibility,user satisfaction,and carbon-emissions.A system dynamics model was then developed to reflect the causal feedback relationship between the impact of the carbon market on the investment and operation of power-grid enterprises.The simulation results of a provincial power-grid enterprise analyze comprehensive investment evaluation benefits over a 10-year period and the impact of carbon emissions on the investment and operation of power-grid enterprises.This study provides guidelines for the benign development of power-grid enterprises within the context of the carbon market.
基金supported by Special Scientific Research Fund of Agricultural Public Welfare Profession of China[grant number 200903013]Liaoning Province,Shenyang Agricultural University,high-end talent introduction fund project[grant number SYAU20160003]。
文摘Actinidia arguta is a berry fruit with high nutritional values.To evaluate the comprehensive quality,the fruit weight,titratable acid(TAC),soluble solids(SSC),vitamin C,mineral elements,and taste value of67 accessions of A.arguta were measured,and sensory attributes including olfactive intensity,juiciness,sweetness,sourness,and astringency were assessed.Cluster analysis was carried out based on mineral elements,and principal component analysis(PCA)was used for comprehensive score ranking.The result demonstrated that fruit weight ranged from 3.5 g to 24.2 g,SSC ranged from 11.94%to 20.56%,TAC ranged from 0.15%to 1.20%,and vitamin C ranged from 3.51 g/kg to 230.76 g/kg(fresh weight)among the tested samples.There were significant differences in sourness,sweetness,bitterness,and umami among the 67 accessions based on electronic tongue analysis,and this result was rapidly and objectively characterized by the sensory assessment.The dendrogram was obtained and clustered the accessions into two major clusters,and five principal components were extracted by PCA.Overall,the information provided by this study identified the 10 best germplasm resources for fresh-eating and processing fruits.It can provide theoretical reference for nutritional efficacy evaluation and food development of A.arguta.
基金This study was conducted in accordance with the ethical standards of the Declaration of Helsinki and approved by Shandong Cancer Hospital Shandong Cancer Hospital and Institute(No.SDTHEC2020010012)。
文摘Dear Editor,The RAS gene is one of the most frequent oncogenes in human cancers,with significantly different mutation frequencies.The RAS family contains three isoforms:KRAS,HRAS and NRAS,with the KRAS mutations being more common than the other two.The KRAS mutation rate varies in non-small cell lung cancer(NSCLC)patients of different races:27%in Caucasians[1]and approximately 10%in Asians[2,3].Recently,the U.S.Food and Drug Administration(FDA)approved sotorasib(AMG510)and adagrasib(MRTX849)for the treatment of metastatic NSCLC harboring KRAS G12C mutations.In the face of novel treatment choices for KRAS-mutated NSCLC,it is indispensable to learn more about the systemic treatment of these patients.Clinical studies have shown that Caucasian patients with KRAS-mutated NSCLC had poor outcomes following first-line chemotherapy[4,5].However,studies on treatment outcomes of Asian patients with KRAS-mutated NSCLC are lacking.As the overwhelming majority of cases are diagnosed with lung adenocarcinoma,the standard first-line treatment for metastatic disease is pemetrexed-based doublet chemotherapy in combination with bevacizumab and/or immunotherapy in China.Herein,we investigated the clinical characteristics of KRAS mutation subtypes,co-occurring genomic alterations,and efficacy of first-line pemetrexed-platinum chemotherapy in Chinese KRAS-mutated NSCLC patients.
基金This work was supported by the National Natural Science Foundation of China(32071379,81670047,and 81873422)the Natural Science Foundation of Chongqing,China(No.cstc2020jcyj-msxmX0622)+1 种基金the Project Foundation of Chongqing Municipal Education Committee(KJQN201900405)the NUS Cross Faculty Grant(R279000502133).
文摘Complexing self-assembled DNA nanostructures with various functional guest species is the key to unlocking new and exciting biomedical applications.Cationic guest species not only induce magnesium-free DNA to self-assemble into defined structures but also endow the final complex nanomaterials with new properties.Herein,we propose a novel strategy that employs naturally occurring cationic amino acids to induce DNA self-assembly into defined nanostructures.Natural L-arginine and L-lysine can readily induce the assembly of tile-based DNA nanotubes and DNA origami sheets in a magnesium-free manner.The self-assembly processes are demonstrated to be pH-and concentration-dependent and are achieved at constant temperatures.Moreover,the assembled DNA/amino acid complex nanomaterials are stable at a physiological temperature of 37◦C.Substituting L-arginine with its D form enhances its serum stability.Further preliminary examination of this complex nanomaterial platform for biomedical applications indicates that DNA/amino acids exhibit distinct cellular uptake behaviors compared with their magnesium-assembled counterparts.The nanomaterial mainly clusters around the cell membrane and might be utilized to manipulate molecular events on the membrane.Our study suggests that the properties of DNA nanostructures can be tuned by complexing them with customized guest molecules for a designed application.The strategy proposed herein might be promising to advance the biomedical applications of DNA nanostructures.