Reid, Lancaster, Tuxpeno and Suwan are the most common maize (Zea mays L.) germplasms. Reid × Lancaster and Suwan × Tuxpeno are very important heterotic patterns in temperate areas and tropical areas, respec...Reid, Lancaster, Tuxpeno and Suwan are the most common maize (Zea mays L.) germplasms. Reid × Lancaster and Suwan × Tuxpeno are very important heterotic patterns in temperate areas and tropical areas, respectively. Broadening the genetic basis of maize has usually been conducted in inter-populations formed by crossing temperate and tropical germplasms. Reciprocal recurrent selection (RRS) is a breeding procedure to improve the inter-populational cross of two base populations. The objective of this study was to evaluate the direct and indirect effects of reciprocal recurrent selection on grain yield in the TR (Tuxpeno-Reid) and SL (Suwan-Lancaster) maize populations. The populations and the inter-populational crosses of each selection cycle, as well as two commercial hybrids, were evaluated in four environments. The effect of mean grain yield on TR × SL inter-population crosses was 4.63% (or 0.365 Mg·ha-1) cycle-1. The grain yield of SL increased by 2.78% (or 0.20 Mg·ha-1) cycle-1, but the grain yield of TR essentially did not change. Most changes in other agronomic traits occurred in the desired direction. After 3 selection cycles, the ear tip-barrenness length decreased in TR × SL, TR and SL by 39.70%, 37.50% and 24.57%, respectively, which indicates that the increase in grain yield may be largely due to a decreasing ear tip-barrenness length. The mid-parent heterosis of grain yield of the inter-populational cross increased from 15.49% to 25.96% from C0 to C3. The mean grain yields of TRC3 × SLC3 were 100.01% and 103.88% of the mean grain yields of the commercial single-crosses GD8 and QD16, respectively. The results suggest that Tuxpeno-Reid × Suwan-Lancaster may be possible new heterotic patterns in the southern region of China.展开更多
Grain production space reconstruction referred to the changes in the quantity,quality and pattern of grain produc-tion space caused by functional tradeoffs and conflicts between grain production space,urban-rural deve...Grain production space reconstruction referred to the changes in the quantity,quality and pattern of grain produc-tion space caused by functional tradeoffs and conflicts between grain production space,urban-rural development space,and ecological service space.Exploring tradeoffs between land system functions caused by grain produc-tion space reconstruction was particularly important for ensuring food security,promoting the construction of ecological civilization,and achieving sustainable development.Therefore,this study identified four relationships of land system functions during the process of grain production space reconstruction(1980-2018)in China by using Set Pair Analysis.Research results showed that the reconstruction of grain production space was achieved mainly through three pathways:Grain for Green,deforestation and reclamation,and urban expansion.Generally,ecological service had spatial negative correlation with grain production,economic development and population carrying capacity(P<0.01),but grain production,economic development and population carrying capacity were positively correlated with each other(P<0.01).In the process of grain production space reconstruction,eco-logical services and economic development,ecological services and population carrying capacity had all shown inverse synergies;there was a tradeoffbetween grain production and ecological services,a codirectional tradeoffbetween grain production and economic development,but a strong synergy between economic development and population carrying capacity.However,the functions of land systems only appeared as synergies or tradeoffs,and there were no inverse synergies and codirectional tradeoffs in the separate processes of Grain for Green,deforestation and reclamation,and urban expansion.It can be concluded that the relationships between land system functions were relatively simple in a single process,but it became complex and diverse when multiple processes were integrated for system analysis.展开更多
Zoo-archaeological and genetic evidence suggest that pigs were domesticated independently in Central China and Eastern Anatolia along with the development of agricultural communities and civilizations.However,the gene...Zoo-archaeological and genetic evidence suggest that pigs were domesticated independently in Central China and Eastern Anatolia along with the development of agricultural communities and civilizations.However,the genetic history of domestic pigs,especially in China,has not been fully explored.In this study,we generate 42 complete mitochondrial DNA sequences from~7500-to 2750-year-old individuals from the Yellow River basin.Our results show that the maternal genetic continuity of East Asian domestic pigs dates back to at least the Early to Middle Neolithic.In contrast,the Near Eastern ancestry in European domestic pigs saw a near-complete genomic replacement by the European wild boar.The majority of East Asian domestic pigs share close haplotypes,and the most recent common ancestor of most branches dates back to less than 20,000 years before present,inferred using new substitution rates of whole mitogenomes or combined protein-coding regions.Two major population expansion events of East Asian domestic pigs coincided with changes in climate,widespread adoption of introduced crops,and the development of agrarian societies.These findings add to our understanding of the maternal genetic composition and help to complete the picture of domestic pig evolutionary history in East Asia.展开更多
This paper aims to address the problem of supervised monocular depth estimation.We start with a meticulous pilot study to demonstrate that the long-range correlation is essential for accurate depth estimation.Moreover...This paper aims to address the problem of supervised monocular depth estimation.We start with a meticulous pilot study to demonstrate that the long-range correlation is essential for accurate depth estimation.Moreover,the Transformer and convolution are good at long-range and close-range depth estimation,respectively.Therefore,we propose to adopt a parallel encoder architecture consisting of a Transformer branch and a convolution branch.The former can model global context with the effective attention mechanism and the latter aims to preserve the local information as the Transformer lacks the spatial inductive bias in modeling such contents.However,independent branches lead to a shortage of connections between features.To bridge this gap,we design a hierarchical aggregation and heterogeneous interaction module to enhance the Transformer features and model the affinity between the heterogeneous features in a set-to-set translation manner.Due to the unbearable memory cost introduced by the global attention on high-resolution feature maps,we adopt the deformable scheme to reduce the complexity.Extensive experiments on the KITTI,NYU,and SUN RGB-D datasets demonstrate that our proposed model,termed DepthFormer,surpasses state-of-the-art monocular depth estimation methods with prominent margins.The effectiveness of each proposed module is elaborately evaluated through meticulous and intensive ablation studies.展开更多
Now,widely distributed modern cats are the descendant of wildcat(Felis silvestris lybica),which are assumed to have originally taken advantage of resources in human settlements,before being tamed in the Near East via ...Now,widely distributed modern cats are the descendant of wildcat(Felis silvestris lybica),which are assumed to have originally taken advantage of resources in human settlements,before being tamed in the Near East via a commensal pathway(Driscoll et al.,2007;Larson and Fuller,2014).展开更多
Background: The antineoplastic activity of Chelidonium majus has been reported, but its mechanism of action (MoA) is unsuspected. The emerging theory of systems pharmacology may be a useful approach to analyze the com...Background: The antineoplastic activity of Chelidonium majus has been reported, but its mechanism of action (MoA) is unsuspected. The emerging theory of systems pharmacology may be a useful approach to analyze the complicated MoA of this multi-ingredient traditional Chinese medicine (TCM). Methods: We collected the ingredients and related compound-target interactions of C. majus from several databases. The bSDTNBI (balanced substructure-drug-target network-based inference) method was applied to predict each ingredienfs targets. Pathway enrichment analysis was subsequently conducted to illustrate the potential MoA, and prognostic genes were identified to predict the certain types of cancers that C. majus might be beneficial in treatment. Bioassays and literature survey were used to validate the in silico results? Results: Systems pharmacology analysis demonstrated that C. majus exerted experimental or putative interactions with 18 cancer-associated pathways, and might specifically act on 13 types of cancers. Chelidonine, sanguinarine, chelerythrine, berberine, and coptisine, which are the predominant components of C. majus, may suppress the cancer genes by regulating cell cycle, inducing cell apoptosis and inhibiting proliferation. Conclusions: The antineoplastic MoA of C. majus was investigated by systems pharmacology approach. C. majus exhibited promising pharmacological effect against cancer, and may consequently be useful material in further drug development. The alkaloids are the key components in C. majus that exhibit anticancer activity.展开更多
Dear Editor,In 2021,the Delta variant of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)caused the coronavirus disease 2019(COVID-19)pandemic to spread in the UK,Nepal,southeast Asia and elsewhere,which se...Dear Editor,In 2021,the Delta variant of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)caused the coronavirus disease 2019(COVID-19)pandemic to spread in the UK,Nepal,southeast Asia and elsewhere,which seems to be approximately 60%more transmissible than the already highly infectious Alpha variant in late 2020(Callaway,2021).In addition to the high efficiency of the invading infection and the acquired immune escape ability,changes in the aerodynamic characteristics of SARS-CoV-2 aerosols may be another important reason for the Delta variant spread.Previously,it was identified that SARS-CoV-2 can spread through close contact and airborne routes(Guo et al.,2020;Morawska and Milton,2020).展开更多
Bone marrow(BM)microenvironment regulates and supports the production of blood cells which are necessary to maintain homeostasis.In analogy to normal hematopoiesis,leukemogenesis is originated from leukemic stem cells...Bone marrow(BM)microenvironment regulates and supports the production of blood cells which are necessary to maintain homeostasis.In analogy to normal hematopoiesis,leukemogenesis is originated from leukemic stem cells(LSCs)which gives rise to more differentiated malignant cells.Leukemia cells occupy BM niches and reconstruct them to support leukemogenesis.The abnormal BM niches are the main sanctuary of LSCs where they can evade chemotherapy-induced death and acquire drug resistance.In this review,we focus on the protective effects of BM niche cells on acute lymphoblastic leukemia cells.展开更多
文摘Reid, Lancaster, Tuxpeno and Suwan are the most common maize (Zea mays L.) germplasms. Reid × Lancaster and Suwan × Tuxpeno are very important heterotic patterns in temperate areas and tropical areas, respectively. Broadening the genetic basis of maize has usually been conducted in inter-populations formed by crossing temperate and tropical germplasms. Reciprocal recurrent selection (RRS) is a breeding procedure to improve the inter-populational cross of two base populations. The objective of this study was to evaluate the direct and indirect effects of reciprocal recurrent selection on grain yield in the TR (Tuxpeno-Reid) and SL (Suwan-Lancaster) maize populations. The populations and the inter-populational crosses of each selection cycle, as well as two commercial hybrids, were evaluated in four environments. The effect of mean grain yield on TR × SL inter-population crosses was 4.63% (or 0.365 Mg·ha-1) cycle-1. The grain yield of SL increased by 2.78% (or 0.20 Mg·ha-1) cycle-1, but the grain yield of TR essentially did not change. Most changes in other agronomic traits occurred in the desired direction. After 3 selection cycles, the ear tip-barrenness length decreased in TR × SL, TR and SL by 39.70%, 37.50% and 24.57%, respectively, which indicates that the increase in grain yield may be largely due to a decreasing ear tip-barrenness length. The mid-parent heterosis of grain yield of the inter-populational cross increased from 15.49% to 25.96% from C0 to C3. The mean grain yields of TRC3 × SLC3 were 100.01% and 103.88% of the mean grain yields of the commercial single-crosses GD8 and QD16, respectively. The results suggest that Tuxpeno-Reid × Suwan-Lancaster may be possible new heterotic patterns in the southern region of China.
基金conducted under the auspice of National Natural Science Foundation of China(Grant No.41701094).
文摘Grain production space reconstruction referred to the changes in the quantity,quality and pattern of grain produc-tion space caused by functional tradeoffs and conflicts between grain production space,urban-rural development space,and ecological service space.Exploring tradeoffs between land system functions caused by grain produc-tion space reconstruction was particularly important for ensuring food security,promoting the construction of ecological civilization,and achieving sustainable development.Therefore,this study identified four relationships of land system functions during the process of grain production space reconstruction(1980-2018)in China by using Set Pair Analysis.Research results showed that the reconstruction of grain production space was achieved mainly through three pathways:Grain for Green,deforestation and reclamation,and urban expansion.Generally,ecological service had spatial negative correlation with grain production,economic development and population carrying capacity(P<0.01),but grain production,economic development and population carrying capacity were positively correlated with each other(P<0.01).In the process of grain production space reconstruction,eco-logical services and economic development,ecological services and population carrying capacity had all shown inverse synergies;there was a tradeoffbetween grain production and ecological services,a codirectional tradeoffbetween grain production and economic development,but a strong synergy between economic development and population carrying capacity.However,the functions of land systems only appeared as synergies or tradeoffs,and there were no inverse synergies and codirectional tradeoffs in the separate processes of Grain for Green,deforestation and reclamation,and urban expansion.It can be concluded that the relationships between land system functions were relatively simple in a single process,but it became complex and diverse when multiple processes were integrated for system analysis.
基金supported by the Chinese Academy of Sciences(CAS,XDB26000000)the Ministry of Finance of the People’s Republic of China(YSBR019)+3 种基金the National Natural Science Foundation of China(41925009)the Tencent Foundation(through the XPLORER PRIZE)the Howard Hughes Medical Institute(grant 55008731)the Shanghai Qi Zhi Institute。
文摘Zoo-archaeological and genetic evidence suggest that pigs were domesticated independently in Central China and Eastern Anatolia along with the development of agricultural communities and civilizations.However,the genetic history of domestic pigs,especially in China,has not been fully explored.In this study,we generate 42 complete mitochondrial DNA sequences from~7500-to 2750-year-old individuals from the Yellow River basin.Our results show that the maternal genetic continuity of East Asian domestic pigs dates back to at least the Early to Middle Neolithic.In contrast,the Near Eastern ancestry in European domestic pigs saw a near-complete genomic replacement by the European wild boar.The majority of East Asian domestic pigs share close haplotypes,and the most recent common ancestor of most branches dates back to less than 20,000 years before present,inferred using new substitution rates of whole mitogenomes or combined protein-coding regions.Two major population expansion events of East Asian domestic pigs coincided with changes in climate,widespread adoption of introduced crops,and the development of agrarian societies.These findings add to our understanding of the maternal genetic composition and help to complete the picture of domestic pig evolutionary history in East Asia.
文摘This paper aims to address the problem of supervised monocular depth estimation.We start with a meticulous pilot study to demonstrate that the long-range correlation is essential for accurate depth estimation.Moreover,the Transformer and convolution are good at long-range and close-range depth estimation,respectively.Therefore,we propose to adopt a parallel encoder architecture consisting of a Transformer branch and a convolution branch.The former can model global context with the effective attention mechanism and the latter aims to preserve the local information as the Transformer lacks the spatial inductive bias in modeling such contents.However,independent branches lead to a shortage of connections between features.To bridge this gap,we design a hierarchical aggregation and heterogeneous interaction module to enhance the Transformer features and model the affinity between the heterogeneous features in a set-to-set translation manner.Due to the unbearable memory cost introduced by the global attention on high-resolution feature maps,we adopt the deformable scheme to reduce the complexity.Extensive experiments on the KITTI,NYU,and SUN RGB-D datasets demonstrate that our proposed model,termed DepthFormer,surpasses state-of-the-art monocular depth estimation methods with prominent margins.The effectiveness of each proposed module is elaborately evaluated through meticulous and intensive ablation studies.
基金supported by the Chinese Academy of Sciences(CAS)and the Ministry of Finance of the People Republic of China(YSBR-019 and XDB26000000)the National Natural Science Foundation of China(41925009)+1 种基金the Howard Hughes Medical Institute(55008731)the Tencent Foundation(through the XPLORER PRIZE)。
文摘Now,widely distributed modern cats are the descendant of wildcat(Felis silvestris lybica),which are assumed to have originally taken advantage of resources in human settlements,before being tamed in the Near East via a commensal pathway(Driscoll et al.,2007;Larson and Fuller,2014).
基金the National Key Research and Development Program of China (No. 2016YFA0502304)the National Natural Science Foundation of China (Nos. 81673356 and U1603122)the 111 Project (No. B07023).
文摘Background: The antineoplastic activity of Chelidonium majus has been reported, but its mechanism of action (MoA) is unsuspected. The emerging theory of systems pharmacology may be a useful approach to analyze the complicated MoA of this multi-ingredient traditional Chinese medicine (TCM). Methods: We collected the ingredients and related compound-target interactions of C. majus from several databases. The bSDTNBI (balanced substructure-drug-target network-based inference) method was applied to predict each ingredienfs targets. Pathway enrichment analysis was subsequently conducted to illustrate the potential MoA, and prognostic genes were identified to predict the certain types of cancers that C. majus might be beneficial in treatment. Bioassays and literature survey were used to validate the in silico results? Results: Systems pharmacology analysis demonstrated that C. majus exerted experimental or putative interactions with 18 cancer-associated pathways, and might specifically act on 13 types of cancers. Chelidonine, sanguinarine, chelerythrine, berberine, and coptisine, which are the predominant components of C. majus, may suppress the cancer genes by regulating cell cycle, inducing cell apoptosis and inhibiting proliferation. Conclusions: The antineoplastic MoA of C. majus was investigated by systems pharmacology approach. C. majus exhibited promising pharmacological effect against cancer, and may consequently be useful material in further drug development. The alkaloids are the key components in C. majus that exhibit anticancer activity.
基金financially supported by the Beijing Nova Program(Z211100002121064)Fujian Province Health Science and Technology Project (2020CXB050)
文摘Dear Editor,In 2021,the Delta variant of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)caused the coronavirus disease 2019(COVID-19)pandemic to spread in the UK,Nepal,southeast Asia and elsewhere,which seems to be approximately 60%more transmissible than the already highly infectious Alpha variant in late 2020(Callaway,2021).In addition to the high efficiency of the invading infection and the acquired immune escape ability,changes in the aerodynamic characteristics of SARS-CoV-2 aerosols may be another important reason for the Delta variant spread.Previously,it was identified that SARS-CoV-2 can spread through close contact and airborne routes(Guo et al.,2020;Morawska and Milton,2020).
文摘Bone marrow(BM)microenvironment regulates and supports the production of blood cells which are necessary to maintain homeostasis.In analogy to normal hematopoiesis,leukemogenesis is originated from leukemic stem cells(LSCs)which gives rise to more differentiated malignant cells.Leukemia cells occupy BM niches and reconstruct them to support leukemogenesis.The abnormal BM niches are the main sanctuary of LSCs where they can evade chemotherapy-induced death and acquire drug resistance.In this review,we focus on the protective effects of BM niche cells on acute lymphoblastic leukemia cells.
